
;»i$iHtijt^«f>iiii^>imiii: 



LIBRARY OF CONGRESS. 

%P itipinB^fn 



UNITED STATED OF AMERICA. 



Machinery Pattern Making 



CONTAINING 



FULL SLZE PROFLLES OF GEAR TEETH 



AND 



FINE Engravings on Full-Page Plates, Illustrating Manner of 

Constructing Numerous and Important 

Patterns and Core Boxes 



yo -ey 



p. S.' DINGEY 

PRACTICAL PATTERN MAKER AND MECHANICAL DRAFTSMAN 



376 3fine fflluetrations 




NEW YORK 

JOHN WILEY & SONS 

53 E. Tenth Street 



Copyright, 1891 
By p. S. dingey 






171, 173 Macdougal Street, New York 



^"^160 



NOTE. 



Most of the matter in this book was written expressly 
for the American Machifiist, to whose courtesy we are 
indebted for some of the illustrations. Mr. Dingey 
has, however, revised many of his drawings and much 
of the matter, adding some valuable items. 

WILEY & SONS. 



PREFACE. 



It is assumed that those who will read this book do not 
need the rudiments of pattern making presented, therefore 
the elementary part of the business, which to most pattern 
makers is so distasteful, has been omitted. The author has 
not laid down any cast iron rules as to the methods set forth 
of doing work, and desires that the contents be accepted as 
suggestions ; at the same time it must be understood that he 
has not shown a number of ways and means for experimental 
purposes, but that which is given is practicable, and the result 
of practice, and of over twenty years experience in the 
business. 

The object of this book has not been to teach pattern 
making, for that can never be done through a book, but to 
discuss methods. 

There are some who regard with a great deal of jealousy 
anything that comes to them about the practical part of their 
trade through a book. Then there are others that scarcely 
ever open a book to read or study, that condemn all books, 
treating them with contempt, and passing sentence on the 
writers who dare write on anything, the fringe of which their 
small minds might have grasped. For the latter this book is 



PREFACE. 

not intended. With the former there is some reason for the 
feeling that exists in their minds, and it may be found in the 
fact, that, from time to time, there have been good writers, 
men of intelligence, those whom we should always honor and 
respect, who have written on the practical, when only pos- 
sessing the theoretical knowledge of their subject. 

In the present volume everything of a visionary kind has 
been avoided, and the author has presented such subjects as 
he believes will be interesting to pattern makers and those 
of the machinery business generally. 

P. S. DINGEY. 
Chicago, III. 



CONTENTS. 



The Pattern Maker and His Trade, .... i 

The Pattern Shop — Its Position, Size, and Requirements, - 5 

Marking and Recording Patterns, ..... g 

Printing-Press Cylinders, - 13 

Differential Chain Pulleys, - - - - - - 15 

A Handy Tool for Laying Out Hexagon Nuts, - - 18 

How TO CAST Journal Boxes on Frames, ~ - - - 19 

How TO strike an Arc by the aid of Three Points, - 20 

Key-Heads for Motion Rods — The way to lessen the cost of 

their production, 22 

Elbow and Tee Pipes — A quick method for turning the patterns 

aud core-boxes in the Lathe, ..---. 24 

Slide Valve Cylinders, 26 

Corliss Cylinders — With a full description, showing how to 
construct patterns and core-boxes which can be changed at 

short notice for different stroke Engines, .... 29 

Fly Wheels — Different styles, - 36 

Engine Frames — How to build the pattern to serve for various 

strokes, .--.-----. 4.0 

Spur Gears — How the teeth should be made, - - - - 44 

Bevel Gears — The manner of laying them out, - - - - 48 

How TO LAY out THE THREAD OF A WoRM FOR THE PATTERN, 5 1 

Worm Wheels — The way to get the angle of teeth and the 

manner of fastening them on, 53 



CONTENTS. 

Sweeping Straight Winding Drums, 56 

Making Winding Drums from Patterns — Method of cutting 

the groove, 5^ 

Making Sheaves from Core-Boxes, 60 

Making Sheaves from Patterns, 65 

Sheaves with Wrought Iron Arms — An original way of 

making the Hub, - - 68 

A Machine for Sweeping Conical Drums — Designed by the 

author, ----------70 

Gear Teeth — One hundred and Twenty-eight full size different 
profiles of Gear Teeth from i^^ to 3^^ Pitch, suitable for gears 

having from 14 to 800 teeth, ------ 74 

Table showing at a glance the required diameters of Gear Wheels 

for a given number of teeth and pitch, - 76, 77, 78, 79, 80, 81, 82 

Weight of Cast Iron Pipe, - 83, 84 

" " Cast Iron Balls, ^3 

" " Round Cast Iron, 85 

" " Square " " 85 

" " Flat «' " 86 

« " Superficial Foot of Cast Iron from %^^ to 2^^ thick - 86 

« " Round Lead, 87 

" " Square " 87 

Binary and Decimal Fractions, 87 

Table which gives distances to open a 2 ft. rule for obtaining angles 

from 1° to 90°, - 88 

Metric Measure reduced to inches, 89 



THE PATTERN MAKER AND HIS TRADE. 

A THEORETICAL knowledge of moulding, with an 
ability to read drawings well, are indispensable to a good 
pattern maker. He has to know how the pattern is to 
be moulded before he can do much, and to see the 
machine, or parts of it, mentally, just as the draftsman 
sees it. 

In many trades, that which is most necessary is to 
become an expert in handling the tools. This is not 
so in pattern making. There is something far more 
important than merely cutting wood. 

In many patterns it is not so much a question of 
workmanship, as knowledge. A pattern, after it is made, 
may be duplicated by any ordinary wood worker ; fine 
workmanship may not have been the all-important, and 
yet none but a first-class pattern maker could have 
planned and made it. 

On the other hand, there is much that calls for fine 
workmanship and less scheming. This is no doubt 
true, more or less, in all trades, but it is especially so 
in pattern making, and this is why I say that pattern 
making is not merely cutting wood. From the very na- 
ture of the trade, a pattern maker is a good worker in 
wood, because he is accustomed to work to finer meas- 
urements than the ordinary wood worker. 

I think the responsibility that rests upon the pattern 



2 PATTERN MAKING. 

department, as to whether work turns out right, is equal 
to that of the drawing room ; for while the draftsman is 
responsible for the design, upon the pattern maker rests 
a large proportion of the responsibility of executing cor- 
rectly that which has been put upon paper. 

The liability to mistakes is reduced considerably when 
the machinist takes hold where the pattern maker has 
left off; the machinist's part is no doubt the most impor- 
tant as to the workmanship and right working of the 
machinery ; he can make it good, bad, or indifferent ; but 
mistakes in measurements he is not so liable to as the 
pattern maker, because the machinist has the casting, 
and is given the drawing of it with instructions to finish 
to drawing. 

When a pattern maker is given a drawing, he has to 
imagine the casting before him, and build something 
that will produce it ; it may be called a pattern, but often 
it is really not a pattern of what is wanted, because of 
the complexity of the casting ; it is sometimes all core- 
boxes and no pattern, and here is where the responsibili- 
ty comes in, and will, I think, explain why the pattern 
shop is often the birth-place of mistakes. 

Of course, mistakes ought not to occur ; but as long 
as pattern makers are fallible, they will occur sometimes, 
though the utmost precaution be taken. I am always 
suspicious of the man that never makes mistakes ; he is 
not to be trusted ; but I have no sympathy for those care- 
less pattern makers who are constantly making blunders, 
and who think when their patterns come within an eighth 
of an inch it is near enough. 

From the nature of the trade of machinery pattern 



PATTERN MAKING, 3 

making, there is more danger of errors being made in 
that branch of machinery building than others, and the 
careful, industrious, workman, who seldom makes an 
error, is worthy of consideration when he does happen to 
be caught, for such a man usually feels bad enough over 
his mistakes, without having anyone make him feel 
worse. 

Owing to the advance made in mechanical arts, pat- 
tern making is becoming one of the most important 
branches in machinery building. It is often underrated 
by a class of machinists who think that because a pattern 
maker is not called upon to work in iron, and to one- 
hundredth or one-thousandth part of an inch, that there 
is not much in pattern making; and yet the pattern 
maker is as much of a machinist, in reality, as those 
generally known as such. 

The onward march of improvements in machinery 
demands that the pattern maker must keep right up 
abreast with the times, although he is considered "a 
necessary evil " among manufacturers. 

There is a great deal of machinery now constructed, 
the coring of which is so complicated that it taxes the 
ingenuity of both pattern maker and moulder to know 
how it can be made at all — the winding passages and 
secret chambers that are wanted in some castings, are 
worse than those we read about in books. The old fash- 
ioned idea of bolting on an arm here, and screwing on a 
bracket there, are fast dying out. The modern plan is 
to make a machine with as few pieces as possible, thus 
making the pattern more difficult to build. 

There are many patterns that require little or no 



4 PATTERN MAKING. 

knowledge of pattern making to make, but I would not 
advise anyone, because he has made a few such patterns, 
to pose as a pattern maker ; there are those who do. I 
have had some experience with them, and hope always 
to be delivered from such. They are a worry to any 
foreman — he is in constant fear that with all his watch- 
ing, the would-be pattern maker will make some serious 
blunder that will cost the firm a considerable sum of 
money — for a mistake in the pattern means a mistake in 
the casting, and as an old employer of mine used to say: 
" Cast iron mistakes are rather serious things." 

The fact that there are so many different ways of 
moulding, gives a great field for study for the pattern 
maker, as to the best way of making a pattern ; but when- 
ever a complicated piece of work is to be done, the 
moulder should be consulted, and I do not think that 
the pattern maker will lose any of his ideas by consulting 
with his brother, the moulder, and while the practical 
parts of the two trades are as unlike as possible, yet there 
is a connection between the moulder and the pattern mak- 
er that is inseparable. If discussion is necessary, let it be 
carried on intelligently, each respecting the other's opin- 
ions. Wherever this is done, good is sure to result, and 
the chances are that the best way of doing a job will be 
arrived at. There are those who are so eager to advance 
their own ideas and have them carried out, that they are 
unwilling to consider those of others ; such persons are 
not likely to be very profitable to any concern, for they 
think more of airing their own genius than of arriving at 
any results that might be of practical value. 



PATTERN MAKING. 



THE PATTERN SHOP. 

ITS POSITION, SIZE, AND REQUIREMENTS. 

The question has often occurred to me why pattern 
shops are located on the upper floor of a building, as 
they usually are. The foundation for fast running ma- 
chinery is anything but good on an upper floor, besides 
being very inconvenient for getting patterns up and down. 
It also is risky business turning a large pattern in a lathe 
whose only foundation is an upper floor that springs 
with every motion of the machinery ; the chances that 
pattern makers will take when turning a large pattern 
under these conditions are great. The ground floor is a 
much better location for a pattern shop. 

Large face lathes for turning large diameters cannot 
be too rigid, but ofttimes the trembling of the face plate 
is caused by too small an arbor, or the bearings may be 
too close together. 

Plenty of room and light are two essentials that are 
generally lost sight of in arranging for a pattern shop. 
This shop is sometimes called the pattern room, and I 
suppose it is thus named, from having, as is often the 
case, such a small space set apart for that purpose, that 
it has scarcely deserved the name of shop. 

The nature of the trade, in a large measure, determines 
the size pattern shop a firm requires. A firm of large 
dimensions making specialties does not need such a large 



6 PATTERN MAKING. 

pattern shop, as a smaller one that builds engines and 
general machinery. It is more to this latter class of 
manufactories, employing about twelve or fourteen pat- 
tern makers, that reference is made. 

Go into a number of manufacturing concerns, and in 
nine out of ten, it will be found that the pattern makers 
are working so closely together as to prevent them from 
getting around their work in a proper manner ; and it is 
surprising how a job may be impeded for lack of room 
to build it. 

When it happens that there is a run of large work, 
then it is that the oft repeated expression is heard " We 
ought to have a larger pattern shop." It is granted that 
shops are situated on such valuable property sometimes, 
that a limited space only can be allotted to each depart- 
ment ; but this does not do away with the fact mentioned. 
In these days of sharp competition, the firms that are not 
cramped for room are the successful competitors in the 
machinery business. 

A pattern shop about 75 ft. x 50 would be a convenient 
size for working the number of men named. 

The machines should not be located all over the shop, 
but at one end within a reasonable working distance of 
each other. 

Among the requirements of such a shop would be a 
face lathe for turning large patterns, 30'' lathe with bed 
about 18 ft. long, \6" lathe for small work, combination 
circular saw table, plain saw table, with saw about \2" di- 
ameter, band saw, jig saw, surface planer, Daniel's plan- 
er, two or three Fox Trimmers, and about six dozen 
(rather more than less) of assorted clamps. I mention 



T ) 



Fig. 1 




FMoifx vmw 



Flfj. 2 




BJLCK VIEW 

C in. STROKE:, 3 in. RISE: BED 6 x 15 inches: 
For SMALL PATTERN WORK. 

FOX'S TRIMMER, 



Weight 25 lbs: 



PATTERN MAKING. y 

this smaller item of clamps in order to insure a plentiful 
supply. Much time is frequently lost by men waiting 
on each other for clamps. 

The Daniel's Planer is a machine that no pattern shop 
of any pretentions should be without. For surfacing 
stuff for pattern makers this machine has no equal, espe- 
cially when knives are kept sharp, and a good supply 
should always be on hand. 

The Trimmer mentioned is also a very valuable addi- 
tion to the pattern shop, in fact, it has come to be a 
standard tool, and the shop that is without one is away 
behind and had better hurry up and get at least one. 

I believe the success of this machine and its being 
adopted so generally in pattern making, is due to the 
fact that it was invented by a pattern maker who de- 
signed it at the time for pattern making. The Trimmer 
has certainly done away with a great deal of the paring 
that used to done with a chisel, and which was. exceed- 
ingly laborious, as most of my readers know, especially 
when cutting end-way of the grain. For building up 
segment work the Trimmer has become almost an indis- 
pensable tool, and will cut as straight and as clean as it is 
possible to cut wood. Figs, i and 2 are two views of the 
smallest size Trimmer made by the Fox Machine Co., 
Grand Rapids, Mich. The illustrations will give the nec- 
essary explanation and will be readily understood. The 
Company make several sizes and the most fastidious 
" wood butcher " can be suited. 

It is not necessary to go into the details of pattern 
shop requirements, but there is a mechanical paper pub- 
lished that ought to be considered a requirement for 



8 PATTERN MAKING, 

pattern makers, and that is the American Machinist. 
There is no doubt but that this is the best and cheapest 
technical educator we have, for it contains more practical 
ideas for doing work in all the branches of the machinery 
business than most papers. 



PATTERN MAKING. 



MARKING AND RECORDING PATTERNS. 

The practice of fixing a mark or symbol on a pat- 
tern to distinguish it from others, is an excellent one. 
The pattern department of any firm cannot afford to dis- 
regard the marking and recording of its patterns. In many 
places a large stock is accumulated, regardless of any 
system; the man who looks after them calls it" Red Tape" 
to mark patterns and record them, and says, " I know 
where to find any pattern without any such nonsense ; " 
at the same time they may be piled together like a lot of 
kindling-wood. What this rule of thumb individual says 
about knowing where to find any pattern may be true, 
but should any unforeseen circumstance remove him, 
who is to find the patterns and know about each, then ? 

The disadvantage that such a firm labors under 
through not adopting some system of marking and re- 
cording is great. To those who have no system I would 
recommend the following : — 

Fix a raised letter and number on the pattern, so that 
it shall appear in the casting. The letter is to designate 
the class of machinery, or it may be used for a certain 
machine ; the number, to distinguish one part from 
another. The mark that each pattern gets should also 
be put on the drawings. This is not generally done, but 
I think if it were, it would greatly facilitate the work in 
the machine shop. The method which I worked for 
many years is shown by the sample entry of patterns 



10 PATTERN MAKING. 

given on page 1 1. The column "pattern at" will be 
found very useful to those sending out their patterns ; it 
is intended to show where the patterns are. In connec- 
tion with this column an index is made showing the 
names of firms with whom business is done. Each firm 
is given a number, as shown ; when a pattern is sent out, 
the number corresponding to the firm it is sent to is 
marked with lead pencil in the column, " pattern at," and 
opposite, the pattern that is sent out ; when it is returned 
the lead pencil mark is rubbed out, showing that it has 
been returned and stored in its place. 

It often happens that in a set of patterns for a certain 
machine, there are those that will do for other machines; 
in such cases an entry should be made in the sched- 
ule of each machine that this piece will suit, giving the 
same letter and number of the pattern. 

There is always a large number of miscellaneous pat- 
terns that cannot be so well classified, yet many of them 
are often used and need marking ; these may be given a 
symbol and entered under the head of " miscellaneous." 

There are also some rough patterns made, the kind 
that is generally " wanted to be cast to-day." All mould- 
ers are acquainted with this kind. It is no use recording 
such patterns, as they are seldom used the second time ; 
in fact, I think the best way to deal with this class is to 
break them up. 

With large manufacturers carrying patterns for a num- 
ber of different machines and many classes of machinery, 
the question may arise what to do when the alphabet is 
exhausted. When that happens, two letters can be used 
to designate a machine or a class, commencing with AB- 



PATTERN MAKING. 



II 



Sample Entry of Patterns. 

18' AND 20" Corliss Engines. 



>< 
in 


NAME OF PART. 


° 

z " 
5 H 

1 


H 
X 

C 


z 

< 


REMARKS. 


A. 1 


CAST IRON. 

Frame for i8^^ and 20^^ 
Engines, 


Pattern arranged 
it may be set for 
strokes. 


so that 
various 


" 2 


18^^ Cylinder, - . - - 


1 






(( u 


(( 


« 3 


\V' Cylinder Head, - - 


1 




1 






" 4 


20^^ Cylinder, - - - - 


1 






Arranged to be 
various strokes. 


set to 


Etc. 


BRASS. 












A. 41 


Key Heads for Motion 
Rods, etc., - - - - 


10 










" 42 


Connecting Rod Brass, - 


1 




2 


Cross Head End. 




" 43 


(< (( (( 


1 






Crank Pin End. 




Etc. 


CAST STEEL. 












A. 51 


Cross Head, - - - . 


1 




3 






" 52 


Eccentric Rod Nut, - - 


2 










" 53 


Cross Head Nut, - - - 


1 











INDEX OF FIRMS AND THEIR NUMBERS. 

1. Eddy Foundry Co. {Iron), Chicago. 

2. Thomas Bros. M'f'g. Co. {Brass), Chicago. 

3. Eureka Cast-Steel Co. {S(eel), Chester, Pa. 



12 PATTERN MAKING. 

AC-AD, etc., until through the alphabet again; then 
begin with BC-BD-BE, and so on ; thus, it will be seen 
that it is possible to have a large combination of distinct 
and separate classes without confusion. 

The advantage of recording and marking patterns is 
that it facilitates ordering the castings and helps to pre- 
vent confusion in the foundry. When the order for 
castings is written out (as it always should be) for the 
foundry, the mark corresponding to that on the pattern 
is put on the order so that the moulder and the pattern 
maker cannot misunderstand each other by naming 
things differently. Again, when a pattern has a particu- 
lar mark, every loose piece (and sometimes there are a 
great many) belonging to the pattern, and also the core- 
boxes, can be stamped with a mark corresponding to the 
pattern. The benefit of this is apparent. There is often 
much trouble caused by not knowing where a certain 
loose piece belongs, and castings are frequently made 
minus a piece just because the moulder did not know 
that it belonged to the pattern ; but if every piece is 
marked as I have said, it leaves no excuse for such omis- 
sions. The raised letters that are nailed on the pattern 
help greatly in checking the castings when received. 
Especially is the marking of patterns necessary for this, 
as gentlemen of the quill profession, who generally check 
the goods, are not usually acquainted with the names of 
the parts of machinery. Also by this method the finding 
of patterns is rendered easy even to a stranger; that is if 
the shelves where patterns are stored are marked with 
the letter corresponding to the class. 

Every firm, large or small, should have some such 
system as I have described. 




Fi(/- 0. 



Fig. 7. 




FRINTING-PRESS CYLINDERS. 



PA TTERN MAKING, \ 3 



PRINTING-PRESS CYLINDERS. 

Some printing-press cylinders have the ends bored 
out and a short shaft pressed into each end, while others 
are made with the shaft and cylinder cast in one. Fig. 
3 is a section and end view of the latter. 

A great deal of trouble is often experienced In getting 
perfect castings for these cylinders, and to insure good 
castings they are cast on end in dry sand, or at least they 
should be ; but in spite of all the preventives used against 
blowholes, dirt, etc., a cylinder will sometimes reveal 
defects when the first cut is being taken off in the lathe. 

Though cast on end, the cylinder is moulded on its 
side, so that the pattern is made in halves in the ordinary 
way, as shown in Fig. 4. 

As an extra precaution against defects an additional 
piece five or six inches long is cast on the end, as shown 
in Fig. 3 from a to b., the pattern therefore should be 
made that much longer. 

The extra length will receive the impurities of the 
metal which rise to the top when pouring. It is made 
thicker on the ends, so that it shall form a head which 
will exert a pressure, thus helping to produce a clean 
and sound casting. 

Figs. 5, 6, and 7 are three views of the core-box. 
The end view, Fig. 5, shows it to be built up with staves, 
which are nailed to three crosspieces, A, B, C. The 



14 PATTERN MAKING, 

box is strengthened by running four strips, c, d, e, /, 
lengthwise on top: and bottom of the box, fastening them 
to the crosspieces. 

Two of the arms in each set are let in about ^'' on 
the inside to keep them from being rammed out of place, 
but a dowel pin is put in each of the arms that go in the 
bottom of box. 

This is a very plain and simple job in pattern making 
and needs no further comment. 



Fiu. 0. 



Fi'j.lO. 



I Fiy. 8. 




Fig. 11, 

1^ 







Fi(/. 12, 






a 



m 



::^ 



a 



SI73 



II 



DIFFERENTIAL CHAIN WHEELS. 



PATTERN MAKING, 1 5 



DIFFERENTIAL CHAIN PULLEYS. 

When the groove in a chain wheel or pulley is made 
to fit the links of a chain it is sure to be an expensive 
pattern, especially when made double, like those used in 
Weston's Differential Pulley Blocks. 

Figs. 9 and 10 are two views of one of this kind of 
pulley. Fig. 10 shows a half section and the pockets for 
the chain. Fig. 9 is a section through the groove C, D, 
of the large pulley, which has one more pocket than the 
smaller one. This view also shows how the chain fits 
into the pockets. 

It may not be out of place here to make a few remarks 
about this celebrated Differential Pulley Block that has 
so revolutionized the lifting of heavy weights, and for 
which this kind of pulley was used, in fact, this pulley 
was the main feature of the patent. T. A. Weston was 
in this country when he conceived the idea that led up 
to the Differential Pulley Block. 

While Mr. Weston was at Buffalo, witnessing attempts 
to raise a vessel that had gone down off that city, the 
thought occurred to him that the necessary power could 
be obtained from the Chinese windlass, the rope of which 
winds on two unequal diameters, that is, one half the 
length of the barrel is larger in diameter than the other. 
This is practically what this pulley block is developed 
from. 



1 6 PATTERN MAKING, 

After much scheming, Weston returned to England 
and called on numerous engineering establishments, sub- 
mitting his drawings, but he could find none that would 
take hold and experiment on his block. Finally he called 
into a small job shop where the proprietors themselves 
were working men, paying the extravagant rent of ten 
shillings a week, and employing six men. That firm 
has grown since then and employs as many thousands 
now. I refer to Tangye Bros., Birmingham. 

These brothers labored hard to make the block work, 
and experienced many unexpected difficulties, and when 
they had perfected it and made it a commercial success, 
a new difficulty presented itself in the shape of a law-suit 
in which the Tangyes won. It is pretty hard to conceive 
of any taller swearing than was practised by the would- 
be infringers in this case, but I will return to the pattern 
of the pulley. 

They are sometimes made so that all the links of the 
chain fit into the pockets, but this is an unnecessary 
expense. The links of the chain that set edgewise in 
the pulley do not need to fit into pockets like those 
shown at a, in Fig. 8. If the grooves bb, in Fig. lo, 
be turned deep enough to clear these links and pockets 
made for the other links to set in, it will be sufficient 
to catch the chain, and will work better than otherwise. 

The groove is sometimes formed in a core-box, and a 
print put on the periphery of the pattern, thus making 
fewer partings in the patterns as well as the mould; but a 
much cleaner and better casting can be obtained from a 
pattern with the groove for the chain cut in it. 

Fig. 1 1 is the section of the pattern and shows how it 



PATTERN MAKING. 1 7 

is made. The mould Is also represented with the cope 
lifted off, the partings being at E, F, G. The pattern is 
built up with segments and made in four parts, c, d, e, f. 
As will be seen, the casting is cored out at A. B., in Fig. 
10. 

Fig. 1 2 is a section of the core-box for this core, and 
is parted at H. The core sets into the round prints g. 
g. ; but there are no cope prints, for the reason that it is 
not easy to close the cope over the six round projecting 
cores. In the absence of these cope prints the moulder 
will need to take care that the cope bears on the top of 
these projecting cores enough to prevent the iron from 
running in the vent holes of the core, when pouring. 

This lightening core can be made in halves or whole, 
just as the core-maker chooses. 



1 8 PATTERN MAKING. 



A HANDY TOOL EOR LAYING OUT 
HEXAGON NUTS. 

Fig. 1 3 illustrates a tool for laying out hexagon nuts, 
and is very handy to pattern makers ; the section of it is 
shown at A. The upper part, which is a light steel 
blade, is screwed on the lower part, which is made of 
hard wood and is used in the following manner. After 
turning pattern to long diameter of nut, place the tool on 
pattern like a center square, move it round and mark off 
sides — keeping the two under edges in contact with cir- 
cle — this is better and quicker than dividing off with 
compasses and then marking sides. 



20 PATTERN MAKING. 



HOW TO STRIKE AN ARC BY THE AID 
OF THREE POINTS. 

It is sometimes required to lay off an arc, the radius of 
which is given ; but the radius may happen to be so 
great as to render it inconvenient to locate a center to 
strike the arc from, or the center may be inaccessible 
from various reasons; under these conditions the ques- 
tion arises what to do to get the arc. 

The following is by no means new, yet it is so little 
understood by pattern makers generally, that I think it 
worth while presenting. The all important, in this prob- 
lem, is to know how to get the point C, or the versed 
sine of arc in Fig. i6; this must be calculated before 
anything can be done towards striking the arc. Let us 
suppose the line A B to be , say 4 ft., and to represent 
the chord of an arc whose radius is 20 ft. ; it is required 
to strike this arc without using the center. By using 
the following formula the desired point can be obtained : 
vrznR — '^R^ — c^. This formula need not scare anyone 
who is not familiar with algebraical expressions ; it is 
very simple, let us examine it. v is the versed sine, R, 
the radius, c, the semi-chord, v is what we want to get. 
The formula means that the square of half the chord, 
which is 4 ft., must be deducted from the square of 
the radius, which is 400 ft., this will give 396 ft. ; then 
extract the square root (v) of 396 ft. which is about 



PATTERN MAKING. 21 

19.9! the formula is now reduced to v=R — 19.9. which 
means that 19.9 must be deducted from R, the radius, 
20 ft., this leaves jV of a foot; y^ of a foot is Ii3^''-|-which 
is the required versed sine. 

Having obtained the versed sine of this arc, it is an 
easy matter now to strike the arc — it is done by cutting 
a piece of wood to an angle, two sides of which run from 
point C and through A B\ drive a wire nail at each 
point of A and B in the piece on which the arc is to be 
struck. It will be readily seen now, that, keeping the 
sides of angle against A B, and moving it right and left, 
the arc can be traced by following with a lead pencil the 
point C. The principle of this is the same as many pat- 
tern makers are familiar with — that of using a square 
for a templet when working out a half-circle core-box. 



22 PATTERN MAKING. 



KEY HEADS FOR MOTION RODS. 

AN EASY WAY TO LESSEN THE COST OF THEIR PRODUCTION. 

The cost of getting out brass key heads for motion 
rods may be considerably reduced in the machine shop 
by the pattern maker doing a little scheming and the 
brass moulder exercising care in moulding. 

Figs. 17 and 18 are two views of a key head, with 
block A in place. A dry piece of cherry or mahogany 
should be selected and the pattern made as shown in 
Figs. 19 and 20; it should be in halves, B C being the 
parting line. D E, Fig. 20, are core prints which carry 
the core horizontally. After the core is located a steel 
key is set in the mould into the print a, the cope print b 
bringing the key upright when cope is being closed. 
The box for the core is shown in Figs. 21 and 22 and is 
doweled together at c d, Fig 2 1 ; a key passes through 
this core-box, which makes a groove in the core to re- 
ceive the steel key. 

It is the intention, when the castings of these heads 
are being fitted up, to file the round ends, while the sides 
are to be finished in the machine, therefore the stock 
allowed for machine finish must stop off at/^. 

There need be no fear of chilling the sides of the holes 
through casting steel keys in these heads ; the effect is 
rather the reverse of what would happen in cast iron, for 
it is well known that if the same thing were to be done 




Fig. 18. 





1 


Fiij. S 


?0. 




^^ 




:-:; ; 


JJ> 


D 


J? 








1] " : 







Fig. 32. 



Iflf 

' -' ■■'■ 



HI 



iuMm 



ILu 



KEY HEADS. 



24 PATTERN- MAKING. 



ELBOW AND TEE PIPES. 

A QUICK METHOD FOR TURNING THE PATTERNS AND 
CORE-BOXES IN THE LATHE. 

Making patterns for elbow and tee pipes, If made the 
right way, is comparatively simple, because nearly all 
the work can be done in the lathe. For turning out 
a large number of castings the elbow pattern should be 
constructed as shown in Fig. 23, so that two elbows 
can be moulded together. A ring is turned like Fig. 24, 
the section of it being a half circle, the same size as the 
pipe ; this ring is cut in quarters as shown, and the four 
pieces used to make quarter turns for the elbows. In 
Fig. 23, the two spicket ends A and B, and the sockets, 
with core prints, are turned on one stick and cut off; the 
stick should be sawed off long enough to permit of 
tongues being turned on A and B, and the sockets, for 
fastening them to the elbows ; dowel pins should be ar- 
ranged to come one in each socket, and in the print 
between A and B, as marked. Fig. 25 represents the 
core-box, and, like the pattern, most of the work can be 
done in the lathe and the parts joined together, as shown; 
a piece screwed on the back will hold the parts to- 
gether. The core is generally made in halves, so that 
a full box will not be needed, and therefore only two 
quarters are used for the turns. In some cases these two 
quarters that are left may be used to turn the socket ends 



Fig. 25. 



Fig. 24. 





Fig. 27. 





Fig. 


28. 






■|_ 


j 


1 


\\\\\\\J\ 


^ 




■ 


G^ 


^ 




^^m 


^^==ri^^ 


tr^==+=s^^*s 


=E=: 


S 


r== 


^^^S^ 




ELBOWS AND TEE PIPES. 



26 PATTERN MAKING, 



SLIDE VALVE CYLINDERS. 

Slide valve cylinders are made in a great variety of 
forms. I have chosen and represented here a well-known 
type, of which Figs. 30, 31, and 32 are three views. 
Fig. 3 1 is a cross section through the steam chest and 
exhaust port, and Fig. 32 is a section through the steam 
port. 

The way of making the pattern for this cylinder de- 
pends largely upon the size of it ; if the diameter is to 
be, say less than \2'\ the body of the cylinder may be 
built up solid, but when above that size it would be bet- 
ter to build the pattern with staves, as shown in Figs. 33 
and 34. But one-half of the pattern is shown, which will 
be all that is needed for explanation. An extra thick- 
ness is glued on each stave large enough for turning the 
body of the cylinder to the required diameter, thus 
allowing the prints and the cylinder to be in one, which 
is far better than fastening on the prints. The flanges are 
made thick enough to turn the fillet on the back of them. 
They should be got out, as shown in Fig. 35 ; this will 
prevent the shrinkage of the wood from affecting the 
flanges to any great extent. 

When the body of the cylinder is built up and turned, 
the steam chest is made and fitted on, as seen in Figs. 36 
and 37. The pieces for the exhaust passage A, and 
those to form a thickness over the ports, are also shown 



^zzzM 



'zzszzzzzmm^zzi 









'///////////////////////////////////.'/////// 




Fig. 38. 



Fiff. 30. ^f 



Fig. 37. 




Fig. 43. 



Fig. 44. 




I 


•:^ 


1 


( ■ ' ^ 


---^/r^^-x 


.,._. , -J 



Fig. 45. 





Fig. 41. 



Fig. 42. 



SLIDE VALVE CYLINDERS. 



PATTERN MAKING, 



27 



in place. The fillets at a b, Fig. 36, are cut out of a thick- 
ness that is inserted between the end of the steam chest 
and port pieces ; there is no danger of the fillets coming 
out when made in this way. 

The strips on the steam chest, which giwc an extra 
thickness of metal for the studs, are loose and put on 
with long dowel pins, so that they can be drawn separ- 
ately, also the valve stem stuffing box, c, and the facing, 
d, around the steam opening are loose. The strips are 
shown at e, Fig 37, let in about ^^" around the sides of 
the steam chest; this is done to prevent them being 
rammed out of place after the dowel pins have been taken 
out. The core print / should be doweled on, because 
if it is made fast it is very probable that the moulder 
will tear it off, for it is a great convenience for him to 
have this print to place back in the bottom of his mould 
while dressing it up. 

Figs. 38, 39 and 40 represent the core-box for the 
steam port. Fig. 38 is a side view with the side A 
taken away. The core is swept off on the outside for 
the length of x, but the piece c is made to finish the out- 
side, because the core changes from a circular into a 
a straight part, just where it is entering the steam chest. 
Fig. 39 is an end view of this box, with the end B, in 
Fig. 38, taken away. Fig. 40 is a plan view and will be 
understood from Figs. 38 and 39. 

The exhaust port core-box is made In halves ; one-half 
is shown in Figs. 41 and 42 ; the other half is, of course, 
like this, except that it is made the opposite hand, so 
that the two halves shall fit when put together. The 
dotted line in the end view, in Fig. 42, shows how the 



28 PATTERN MAKING. 

passage is widened to maintain the same area through- 
out ; that is, it is cut down along the part in the direction 
of arrow in Fig. 41. 

The steam chest core-box is made as seen in Figs. 43, 
44, and 45 ; the side and end are taken off in Figs. 43 
and 44, to show the inside ; the piece D that forms the 
valve face is screwed on the bottom, and the sides fit 
over it; this core is the first that is set in the mould, 
then the exhaust and steam port cores are set into i, 2, 
and 3, Fig. 45. 



section thro' A.b! Fig. 47. 




Cross 
Pieces 



. Fig. SO. ? 



Sliding End 7 



Fig. S3, 



J) Fast End 7 



Fig. 49. 




Fig. 52, 



Fig 


.S4, 


^^^^^^^^ 






= ---— ■ 


s?sgr— 




s 

A 




■ ■ '— 


i ■ 


^ 






Fig. Sf. 
CORLISS CYLINDERS. 



PATTERN MAKING, 29 



CORLISS CYLINDERS. 

SHOWING HOW TO CONSTRUCT PATTERNS AND CORE-BOXES 

WHICH CAN BE CHANGED AT SHORT NOTICE 

FOR DIFFERENT STROKE ENGINES. 

It is often required in shops building engines that a 
cylinder pattern be so constructed that it will serve for 
engines of different strokes. To illustrate one way of 
making a pattern like this I have chosen a Corliss Cylin- 
der. Fig. 46 shows the wrist plate side and half section 
of cylinder. Fig. 47 is a section through A B, and Fig. 
48 is a section through A' B'. As both halves of pat- 
tern are almost alike, it will only be necessary to deal 
with one half 

Experience has taught me that -^^" to the foot is 
enough to allow for shrinkage on a job of this kind. 
Use first quality dry lumber ; it will pay to take some 
pains in selecting stuff for this pattern ; for, if the lumber 
is not thoroughly dry, before the pattern is completed, it 
will be found that dimensions are scant. 

By referring to Fig 49, it will be seen, that to make a 
pattern for different stroke engines, I have arranged it to 
slide like a telescope. Fig. 49 is shown pulled apart, and 
illustrates how the pattern is built. Fig. 50 is a section 
of Fig. 49 through C D ; the lagging a b c d e,m Fig. 
50, is taken off in Fig. 49 to facilitate explanation. An 



30 PATTERN MAKING. 

inner box is first made, the length, width, and depth of/ 
g h in Figs. 49 and 50, and doweled together with iron 
dowel plates like sketch. Build out each side of this in- 
ner box for about two-fifths of its length to width G, in 
Fig. 46, then fasten on strongly three cross pieces num- 
bered I, 2, 3. For future reference I will name this the 
" Fast End." 

In Figs. 49 and 50, the outside piece marked 7 should 
be made wide enough for the exhaust passage in Fig. 47. 
Notice that in making the inner core-box the board K is 
cut in two so that one piece may form a part of the slid- 
ing end. On the sides of box, glue and screw two 
guides marked E Fin Figs. 49 and 50; on each side of 
these guides, fit pieces that shall slide over them, and se- 
cure them to the two outside pieces, 7 and 8. This will 
make the sliding end the same width as fast end. Now 
fasten the cross pieces, 4, 5,6, and piece K, to the two 
slides, and be careful not to get any of them glued to the 
box; the lagging a b c d e, m Fig. 50 will hold this 
sliding end together, and, as the pattern progresses, other 
parts will make it secure. The piece i forms the core 
print for coring out the space T, that separates exhaust 
passage from body of cylinder. (See Figs. 46 and 47). 

In Fig. 49 we have now a foundation to build on, and 
have made it the width of G in Fig. 46. At this stage, 
the length of the pattern, when closed for the shortest 
cylinder required, should be the length of the cylinder, 
minus the thickness of two flanges and i\" for fillets on 
back of flanges. Fig. 5 i represents the pattern closed, 
with a filling piece, H, put into it and the framework of 
Fig. 49 all closed up. 



PATTERN MAKING. 



31 



Proceed next to get out the end flanges, valve cham- 
bers, port pieces, etc., and build on. Get out the flanges, 
as shown in Fig. 52, glue on three pieces, /, I, J, ^" 
thick ; this f thickness is for carving the fillets on 
backs of flanges, and makes by far the best job. It must 
be remembered that the cylinder illustrated here is sup- 
posed to be a standard pattern, from which a large num- 
ber of castings may be taken, so that in this case the 
best way will be the cheapest in the end. 

Glue and screw on the end flanges, shown in Fig. 52, 
and the side pieces, a' b' c' d' , Fig. 51, for the valve 
chambers. Build some blocks together, same shape as 
shown in Fig. 53, and fasten them in place>atyy, to 
form the ends for steam valve chambers. For very large 
cylinders these pieces had better be boxed. For the 
ends of exhaust valve chambers, L L, make plain square 
blocks ; now make the exhaust passages the right height, 
by gluing on piece 9 in Figs. 5 1 and 54 ; after this, fit in 
the pieces 10, 11, 12, 13, Fig. 51, that give a thickness 
of metal over the steam and exhaust ports. All is now 
ready for rounding off the corners and side of steam 
passage, and cutting the fillets. 

Check down the two inner edges on ends of valve 
chambers (See Fig. 46). This is to allow the bonnets 
to lap over and cover the joint of the black walnut lag- 
ging, that these cylinders are generally cased in. I have 
said that both halves of pattern were almost alike ; the 
difference between them is, the center piece for bolting 
the wrist plate to is usually on the opposite side of the 
small bosses that take the indicator pipe ; also the valve 
chambers are made about one inch longer on the cope 



32 



PATTERN MAKING, 



side of the pattern than on the drag side; this is done to 
insure solid ends after this extra inch is planed off the 
casting. 

When casting these cylinders, all dirt and flux that is 
in the mould and metal rise to those four high places 
and stick there ; hence, the necessity of extra stock on 
the ends of valve chambers. 

In turning the eight round core prints for the valve 
chambers make those in the cope as much shorter than 
those in the drag, as the extra stock just mentioned; in 
other words, the core prints should measure the same 
length from the joint of pattern on both halves. The 
necessity of this will be seen when we come to make the 
core-boxes. Give these prints plenty of taper, because it 
will help the moulder to feel his way when dropping in 
the cores of valve chambers ; it will also help to bring 
the cores upright when dropping on the cope. 

Now fit on the pieces x and z, to take the exhaust and 
steam flanges (see Fig. 46), and, as these pieces are to 
be removed for sliding the pattern out and in, they must 
only be doweled and screwed on. Screw the core prints 
on these pieces from the back. The center piece, /, Fig. 
46, should only be doweled on. Build up the core prints 
for bore of cylinder, as shown, and turn a flat flUet on 
them at y, Fig. 5 1 . This will prevent crushing the edge 
of sand when putting the core in and dropping on the 
cope. Turn these prints whole and saw in halves with 
band saw after turning them ; for large cylinders it will 
be better to build these prints with staves. We may now 
consider the pattern finished. 

There are many details which are omitted, because 



Fhj. sit.m 




CCRLISS CYLINDERS. 



PATTERN MAKING. 33 

they are such as the pattern maker will naturally run 
against ; so let us leave the pattern and start in on the 
core-boxes for the steam and exhaust passages, valve 
chambers, etc. 

It will scarcely be necessary to enter into the minor 
details of making the core-boxes, seeing that I have 
shown both cores and core-boxes for the steam and ex- 
haust sides of a cylinder. 

However, a few explanations may be necessary. Like 
the cylinder pattern, I have only shown half sections of 
cores; Figs. 55, 56, 57, are three views of the core for 
steam passage and valve chambers. A half core-box is 
all that is needed to make this core, the joint of it being 
on line C D' , and the joint of core-box on line E P . 

Figs. 58, 59, and 60 are three views of the core for 
exhaust passage and valve chambers, also made with a- 
half core-box. 

The core-box for the steam core is constructed as 
shown in Figs. 61 and 62. The port cores, e' f ,\xv Fig. 
57, are made separate, and pasted in; the core prints to 
receive these port cores are seen at e' f in Fig. 62. 
Like the pattern, these boxes are made so that the length 
can be changed. In Fig. 62 the joint, g\ for the length 
of h\ is not glued, there being a tongue or guide for this 
surface to slide in ; the piece, i, is loose, which can be 
taken out, thus allowing the valve chamber part to be 
slipped toward the center as may be required ; on the 
inlet side of this box, the joint m, for the length of <?, 
and the joint ;/, for the length of/, is also made to slide, 
and when the box is to be shortened, the two pieces, r 
and s^ are taken out, which will allow the valve cham- 



34 PATTERN MAKING, 

bers to be slipped toward the center; each side of the 
inlet is alike. The reason there are more loose pieces on 
this side of the core-box than the other, is because the 
inlet must always be located midway between the two 
valve chambers. 

The exhaust core-box of which Figs. 63, 64, 65, 66 
and 6^ are five views, is made open on one side between 
the valve chambers, and as this open side is a plain 
straight surface, it can be swept off with a sweep, as 
shown in Fig. 6y . The valve chambers are round, all 
the way through, in this core, as will be seen by referring 
to Fig. 58. Like the core-box for the steam side, two 
pieces, v, w, Figs. 63, 64, are inserted, for changing the 
length. Fig. dy shows a section of the box ; the side x^ 
is carried above the center line of valve chambers. 

Fig. 60 shows the side of core runs over the center 
line G, H, hence the necessity of carrying one side of the 
box above the center of valve chambers. 

Figs. 65, 66, are two views of the port halves of valve 
chambers, and, like the steam core, the port cores are 
made separate and pasted in. 

The core-boxes for the exhaust and steam ports are 
made like Fig. 68, except that the exhaust port box is 
made thicker than the steam port box. In small size 
Corliss Cylinders, whole core-boxes are sometimes made, 
instead of half-core boxes, but for large cylinders, the 
cores are better made in halves both for convenience of 
making and drying. 

The box for coring out the space that separates the 
body of cylinder from the exhaust passage may be made 
as shown in Figs. 69 and 70. Make the box half the 



PATTERN MAKING. 35 

length of the space. (See Figs. 46 and 47 at T). It 
will be seen that in the center of this space, there is a 
bridge ; to form this, a loose piece, V, Fig. 69, half the 
thickness of the bridge, is made and fitted in the end of 
core-box, and as there must be two right and two left 
hand cores, changing this loose piece to the opposite end 
will give it. It will be found that two other small cores 
are needed, one right-hand and one left-hand, to core out 
between the valve chambers and cylinder on the exhaust 
side. These small cores are really a part of the core for 
coring out the space T, in Figs. 46 and 47, and might be 
made in one core, like the core print shown in Fig. 51, 
but I think it is easier to make them separately. I have 
not shown these small boxes, as they will be readily un- 
derstood without. 

Those who make Corliss Cylinders, will no doubt see 
the advantage of making their patterns to slide the way 
I have shown, as the pattern can be easily and quickly 
changed for different lengths without damaging it. 



36 PATTERN MAKING. 



FLY WHEELS. 

DIFFERENT STYLES. 

Making fly wheels is such an every-day occurrence, 
that it seems almost unnecessary to say anything about 
it, and yet I think something might be said that might 
be of service to some one. 

These wheels are generally cast in halves and bolted 
together, except in the case of a fly wheel with square 
rim, in which case it is generally held together with 
wrought iron links, shrunk on each side of the rim, 
as shown at B, in Fig. 71, or sometimes with cotter-bolts, 
as seen in Fig. 72. 

Fig. 71 is part of a square rim fly wheel, and Fig. 73, 
that of a band wheel. These two wheels are the same 
diameter and of about the same weight. Let it be sup- 
posed each is designed for one size engine ; one cus- 
tomer will want a band wheel for his engine and another 
may want a fly wheel with square rim, and because of 
this, it is proposed to make the same arm core-box, with 
changes, do for both wheels. Fig. 74 is a section of a 
mould for a square rim wheel ; it will be seen that the 
lower and outside part of the*mould are formed in green 
sand, the segment pattern in Fig. 75 being used for that 
purpose. A step is made in this segment at A, so that 
in ramming up, the green sand can be swept off level 




j ^ Fift. SO. ^ 



Fuj. SI. 



FLY WHEELS, 



PATTERN MAKING. 37 

with it ; this makes a level surface on the inside, on 
which to set the cope cores shown in Fig. 74. A pin is 
put through the end that fits over the spindle to prevent 
it from getting away. 

Fig. j6 is a section of the mould for the band wheel ; 
the inside of the rim is all rammed up in green sand, us- 
ing segment in Fig. JJ. Two views of the core box for 
the cope of square rim fly wheels are shown in Figs. 78 
and 79, and the length of the box is from B to C, in 
Fig. 71. Z^, in Fig. "jZ^ is a print to receive the core for 
the link, and as there are to be two right and two left 
hand cores, it must be changed to the other end of the 
box for opposite hand cores. Two views of the core-box 
to form the recesses for links are shown between the 
arms of Fig. 71, and cores made in this box will be set 
in print D and also in a print on the segment. 

The arm core-box, of which Figs. 80 and 8 1 are two 
views, should be made very strong, as it, of necessity, 
gets very rough usage. If this arm box is built the way 
I have shown, and a bolt put at each end to hold the 
sides together, it will stand a considerable amount of 
rough handling before coming apart. The depth of the 
box is governed by the distance of the bolt holes in the 
hub from the center of arm ; in this case a, b, in Fig. 82, 
is the depth ; notice also the box is made longer than it 
is needed for these wheels. This is done that it may be 
used for larger wheels. F, in Fig. 80, is made loose and 
is laid on top of E, which is also loose ; the piece, F, is 
used in the box for the lower half of arm cores, and 
for the upper half it is taken out, because the ends of 
the upper arm cores must lap over the outer edge of 



38 PATTERN MAKING. 

mould in the same manner as the cope cores for the 
rim. (See Fig. 74). 

For the band wheel, E and F are taken out and the 
piece in Fig. 83 substituted. The end of the box is then 
made to fit the inside of the rim for band wheel. The 
length from center of hub to C, in Fig. 73, corresponds 
with the distance from the center to dotted lines, d, e, in 
Fig. 71. The three pieces marked i, 2, 3, are used to 
form the hub in arm core-box. In Fig. 80, / is a half 
round core print and is changed to the opposite side 
when piece numbered 3 is used, and on a wheel having 
six arms there will be twelve cores, four of each from 
the pieces i, 2, 3. In order that the cope cores for the 
rim may fit against the sides of arm cores, two wedge 
pieces, g, g, are fitted against the sides of the box, mak- 
ing that part of the box radial, like the ends of the box 
in Fig. 78 are made. In making the core-boxes, a clear- 
ance, (say i;-J' on a side) should be allowed where the 
cores fit together at the hub and rim ; nine times out of 
ten the moulder has to file these cores to get them in 
position, and it is very provoking to find, when the last 
arm core is being set, that it will not go in place by \" 
or more. 

The box, in Figs. 84 and 85, is to complete the outer 
part of the hub on each side of line a' b' in Fig. 82. // 
h are half round prints that will match /, in Fig. 80, 
when cores are set. 

In Fig. 74, the dotted line, M, represents the surface 
of a level bed that is struck, and which is the first 
thing to be done towards making the mould, but before 
the rim can be made, the core for the end of hub must be 



PATTERN MAKING. 39 

located, the top of it being set flush with the bed, M. 
This core, which forms part of the hub, will be a guide 
to set the lower halves of arm cores, which is the next 
thing to be done. After this, the green sand part of the 
mould is rammed up. 

The band wheel is made in much the same manner, 
except that in Fig. "j^, the level bed is struck off at N 
and the arm cores blocked up to the proper height, and 
the inside of the rim rammed up. 

The outside of the band wheel can be formed by cores, 
like P, being set around. When making the segment, 
it should be made deeper from the center rib to iV, than 
it is to the cope edge. The reason for this is to allow 
for the piece x, that is made on the core, P, x being a 
guide for setting these outer cores, so as to give the 
desired thickness to rim. 



PATTERN MAKING. ' 4 1 

We start the pattern by building up two half round 
pieces, one to be larger in diameter than the other ; the 
smaller will be the diameter of the inside of frame, and 
will therefore serve as a core print, and the larger for the 
outer diameter of frame. The end view of these two 
parts is shown in Fig. 89, their length is from b to c, in 
Fig. 90. Notice that on one end of the larger part, it is 
turned down to the same diameter as the small part ; this 
is for the sliding end to slide on. 

Get the staves out for building the larger part, and 
glue on an extra thickness, forming a step as shown 
in Fig. 91. After building the two parts, then put them 
together and turn, but as one part is larger than the 
other, they must be balanced before turning. It will be 
seen that only the large piece and the end of the smaller 
can be turned ; the remainder of the smaller piece will 
have to be planed off. Next get some staves out like 
Fig. 92 to make the sliding end H, as shown in Fig. 90. 
The length of this will be from d to e. The flange is 
glued up in two courses and fastened around this sliding 
end, H. The end piece that receives the cylinder should 
not be fastened on permanently, as one frame does for 
two or more sizes of cylinders, so that instead of putting 
on and taking off a lining, it is better to make two or 
or three ends for changing. 

In Fig. 90 the pattern is shown arranged for the long- 
est stroke. /^ is a piece bolted on the end at b to give 
more bearing to the sliding end, H. G^ is a filling piece 
built up in three courses so that whenever it is necessary 
to shorten the frame, these two pieces, /^and G, can be 
easily taken out, and the sliding end moved up and 



42 PATTERN MAKING. 

screwed again. On referring to Fig. 86 it will be seen 
that the half of this sliding end that goes around the 
print has to be cut out circular, like the front end in Fig. 
Zy, and moulding fitted around it. In making the mould- 
ing that is shown around the edge of frame it should be 
made loose from the print as far as <?, o, thus making 
strong loose pieces, which are less likely to be broken. 

That part of the frame that covers the print should 
now be fitted on. Having the round part of frame ready, 
get the ribs built on the back by first planing two flat 
places on the pattern where these ribs connect to the 
body, wide enough to take a piece that shall form the 
inner and outer fillets at bottom of ribs ; see/, Fig. 89. 

Fig. 93 shows the large part of pattern ; it is laid on a 
plank that is surfaced; on this plank a center line is 
struck as a guide for getting the other part of frame in 
line with the body; after locating the center line on pat- 
tern to that on the plank, fix a temporary piece, K, on the 
end, and also a piece, Z, the same height. The point, M^ 
shows the full length of frame ; these two pieces, K and 
L, are temporary supports for locating the straight part 
of frame. On these supports square up a center line 
from the plank. The straight part, N, should be flush 
with the two pieces, f J, in Fig. 89, so that the two ribs 
can have a straight bearing from end to end. 

Now is the best time to bore some holes through the 
body of pattern for screwing on the ribs. It will 
strengthen the pattern to glue some dowel pins through 
the body and down into the ribs. Having put this part 
together securely, proceed to fit in the bracket at P, Fig. 
86, remembering that the inside of these brackets should 



PATTERN MAKING. 43 

match the inside of frame. The two lightening holes at 
the back, seen in Fig. %J , are cored. These cores will 
serve to set the main core on. 

Having completed the pattern, make a half skeleton 
core-box for the inside of frame. This box is seen in 
Fio-. 94, of which Fig. 95 is a cross-section. First build 
an end as shown at Q, and though but one-half be 
needed, it will pay to build a full circle and turn it. After 
cutting it in halves, take one and screw on three pieces, 
R, S, T. To R and 5 screw on two other pieces, U and 
V, for the guides. When the core is being made, the 
screws shown are taken out, thus leaving 6^ and F behind 
to be drawn out separately. This skeleton box is 
arranged for the longest, and when changing length of 
frame all the change that the core-box will require is to 
fit a piece in the plain end to the desired length. 



44 PATTERN MAKING. 



SPUR GEARS. 

AND HOW THE TEETH SHOULD BE MADE. 

There are so many ways of making gear patterns that 
it would be extraordinary to show some new way. The 
question is, which is the best way to make a gear pattern 
that will stand a reasonable amount of hammering, not 
be unnecessarily expensive, and so that a casting when 
taken from it will run smoothly. Even on a gear pat- 
tern much unnecessary time may be spent, and is spent, 
that does not make the pattern any better, but only more 
expensive. For instance, dovetailing the teeth on gears 
\\" pitch and above, is unnecessary work. Much time 
can be saved by fastening the teeth on, as shown in Fig. 
96. I have found this way to be cheaper and by no 
means inferior to dovetailing. 

It is often found that after the rim has been turned 
and the teeth dovetailed on, that the wheel runs out; 
there is no doubt that the cutting of the rim and driving 
in the dovetails have to do with this, and yet there are 
men who will argue that a gear cannot be made right 
unless the teeth are dovetailed on. 

By the method shown in Fig. 96, we have the advan- ^ 
tage of getting a fillet at the root of the tooth, which 
cannot be well made on one that is dovetailed on ; in this 
way the tooth is also strengthened and made better for 
moulding, which means a better casting. 

In making the pattern, the blocks for the teeth should 



PATTERN MAKING. 45 

be sawed out first, and then the segments for building 
the rim. These should be laid aside for awhile to allow 
any moisture that is in the wood to dry out, and though 
the stock may be considered ever so dry, it is better to 
do this, and the importance of it cannot be over-esti- 
mated in gear making. 

In the meantime get out the arms and put them to- 
gether ; if the arms are of an oval section, now is the 
time to shape them, because it is far easier to do this 
before fixing them in the wheel. 

Fig. 97 represents the way the arms may be put to- 
gether. It will be seen that tongues are inserted in the 
joints where the arms come together. The grain of 
these tongues should not run parallel with these joints, 
but across. 

Before building on the last two courses of segments 
for the rim, turn the rib that is on the inside (see Fig. 98), 
then build the arms in place, taking care not to fit them 
so tightly as to spring the rim — the remaining courses 
may now be laid up. 

In Fig. 98 I have shown a cast iron flanged bushing ; 
the center of arms is turned out to receive it, and is se- 
cured by one or more screws in each arm. I would 
suggest here that it would be a good thing to have a 
bushing of this kind in nearly all wheels, and that a stan- 
dard sized hole be adopted. All hubs should then have 
a projection turned on them to fit the standard size. 
There would be but little trouble then in changing the 
hubs. 

After turning the rim for the wheel, fit on the blocks 
for teeth, and screw them on from the inside of rim ; then 



46 PATTERN MAKING. 

fit strips between, as shown ; take care not to allow any 
glue to get between the blocks and strips when nailing 
and gluing on the latter, because the blocks have to be 
taken off again to work the teeth out. 

In some cases it may be better to screw on a block 
and fit a strip the right width against the side of block 
before screwing on the next one, but this is purely a 
matter of choice with the pattern maker. 

There is quite a variety of systems employed for lay- 
ing out the profile of gear teeth, and I do not propose to 
enter into any discussion regarding the merits of these 
different systems ; but much of the controversy is so 
hair-splitting that in practice it amounts to nothing when 
applied to cast gears. In some shops the teeth are laid 
out to " suit the eye." Of course this is entirely wrong, 
and, though such gears may run, there will be much 
jarring and friction, which means extra wear and tear, 
and loss of power. 

For general purposes it is desirable to get that form 
of tooth that shall work with the least possible friction, 
and at the same time be interchangeable with any other 
of the same pitch. There are various ways of getting 
this. One good way is by the use of Prof. Robinson's 
Templet Odontograph. Fig. 96 shows how to apply the 
Odontograph. The full lines show it in position for 
marking the face of tooth, while the dotted lines show it 
reversed for marking the root. 

To locate the Odontograph in proper position for the 
face of tooth, " setting " tables are supplied with the 
instrument, which will give the graduation on the Odon- 
tograph to set to pitch line ; but this graduation is not 



PATTERN MAKING. 



47 



all that is needed to set the instrument by. In Fig. 96, 
two dotted lines, c and d, are drawn from the center of 
the tooth, forming a right angle, d being radial ; now, by 
setting the hollow edge of the Odontograph even with 
the line c, and using the graduation referred to. the loca- 
tion is determined for the face of tooth. 

For the flank or root, two lines, a and b, are drawn 
from the side of the tooth, also forming a right angle, b 
being radial ; by the aid of the line a and the " setting " 
for the flank, the Odontograph may now be set for the 
flank. 

When a setting is found for one part of a tooth, the 
instrument should be screwed on a radius rod, which is 
moved around a center pin in the hub, so that in this 
Odontograph we have a ready-made templet for the teeth, 
and are not troubled with getting centers for the points 
of compasses somewhere outside the wheel or between 
the teeth, as sometimes happens. 

While it is very desirable to make gears that are inter- 
changeable, and which are good enough for all ordinary 
machinery, it must be acknowledged that the best form 
of tooth cannot be made by any interchangeable system ; 
of course, I am speaking now of the epicycloidal form of 
tooth. For some special machinery, where it is neces- 
sary to have the best form of teeth, without regard to 
their being interchangeable, the Odontograph is set 
differently from that for the interchangeable. Prof 
Robinson gives extra tables for this purpose, and herein 
lies the value of the Templet Odontograph, and I would 
recommend its being used, especially for coarse pitches. 



48 PATTERN MAKING. 



BEVEL GEARS. 

THE MANNER OF LAYING THEM OUT. 

Before saying anything about the construction of these 
patterns, some explanation should be made about the 
lines that are required. 

Fig. 99 is a section of the gear and pinion to be made, 
and gives the angle at which the two shafts are set. 
Fig. 100 is a face view of the gear. Bevel gears are 
usually made to run at right angles to each other, but 
when occasion requires, they can be made to run at any 
angle. In Fig. 99, a is the angle that is chosen ; the two 
lines representing this angle are the first to be drawn, for 
on these all the others depend. 

Having the angle, the next to be determined are the 
proportion and sizes of gear and pinion. In this case, I 
have made the proportion about 3 to i, pitch i^". 
The gear is 26.8'' diameter, having 56 teeth, the pinion 
9.1 1 '' diameter, with 19 teeth. The pinion is made with 
an odd number of teeth, so that the teeth shall not work 
into the same ones of the gear at every revolution, but 
shall be constantly changing ; the odd tooth is sometimes 
called a " hunting tooth." 

The angle and the dimensions being settled, proceed 
by drawing the line b, at right angles to c. This line b 
is the diameter and the pitch line of the gear. From 
point d lay off e at right angles to // this will be the 



PATTERN MAKING. 49 

pitch line and diameter of the pinion. Draw the center 
line, g, parallel to /; this locates the center, h, towards 
which all the teeth must converge. Draw i, j\ k, the 
center lines of teeth, to h ; on these lines lay off the face 
of the wheels, making the ends of teeth square with the 
center lines, i,j, k. 

The section of the rim, arms, and hub, are now easily 
drawn. The teeth are laid out on larger circles than the 
diameters of wheels, the centers being A and B. These 
centers are obtained by producing the. line representing 
the ends of teeth, or, in other words, making m at right 
angles toy, until it cuts the center lines of gear and pin- 
ion at A and B, The profile of the teeth must be made 
as if the centers of the gear and pinion were at A and B. 
To get the correct thickness of the tooth on the inside, 
the outer thickness must be laid down at n, running the 
sides toward the center, h. The profile of the inside of 
teeth is made after the same manner as the outside. 
Having described the method of drawing out these 
gears, we can pass to the construction of the patterns. 

The rim is built up on a face-plate in a manner shown 
in Fig. loi, and when the work is thoroughly dry, the 
inside should be turned, getting in around at P as far as 
possible. The arms are fitted in the wheel as shown in 
Fig. 102, which should be done before taking the rim off 
the face-plate. There is a thickness of about y^" put on 
each side of the arms to hold them together, also answer- 
ing for fillets ; see Fig. 103. Tongues should be inserted 
at the joints where the arms join at the center, thus 
making, with the pieces on either side, a strong job. It 
is the intention to leave the hub and ribs, DD^ in Fig. 



50 PATTERN MAKING. 

99, loose, so that they can be lifted with the cope, thus 
preventing the mould from tearing down. After fitting 
in the arms, the rim is chucked, as seen in Fig. 104, and 
finished on the outside ready for putting on the teeth. I 
have already described the manner in which gear teeth 
are put on spur gears, and these should be put on in a 
similar way. 

Pinions may be built up hollow or solid ; in this case 
it is not large enough to build hollow, so pieces must be 
glued together with the grain of the wood running with 
the axis of pinion, and large enough to allow the teeth 
to be cut out of same. For larger pinions, the pieces 
can be glued around the periphery, the grain of wood 
running the same way as the teeth, then turned off, and 
the teeth cut as if cutting them from the solid, as before. 



FA TTERN MAKING, 5 I 



HOW TO LAY OUT THE THREAD OF A WORM 
FOR THE PATTERN. 

Let us suppose the pattern for a worm is to be made 
4'' diameter, with a single right-hand thread \y^" pitch. 

First, turn the pattern — which should be in halves — 
to the diameter, aJ' , and to the required length, say 6" , 
see Fig. 106. Do not destroy the centers, because after 
the threads are cut, the pattern can be returned to the 
lathe, and the threads sand-papered on a slow speed ; a 
much better job can be done at sand-papering this way 
than otherwise. After turning the pattern, wrap a piece 
of paper around it and cut to the exact length of circum- 
ference, and also the length of pattern. After doing this, 
take the paper off and lay it flat, as shown in Fig. 105. 

The full lines which are laid off parallel to each other, 
and ly^" apart, represent the center line of thread, or 
pitch. After making these lines, take the paper and 
wrap it around the pattern again, and it will be found 
that the end marked i will meet the end marked 2, and 
4 will meet 3, and 5 will meet 6, and so on, thus making 
one continuous line when wrapped on the pattern ; but 
before gluing the paper to the pattern, mark the thick- 
ness of the thread. Be careful when you have a right- 
hand worm to make, that you do not make it left-hand 
by running the lines the wrong way; I have seen this 
done more than once. If it is to be a right-hand thread, 



52 PATTERN MAKING, 

the lines should run down towards the left-hand, as seen 
in Fig. 105. If it is to be a left-hand, they should run 
down towards the right. 

When a double thread is required, instead of starting 
to draw the lines from the first division to the corner, 
start from the second, as shown by dotted lines. This 
will give a double thread, and, in fact, any number of 
threads can be obtained this way. If the angle of the 
thread is increased twice, two threads are the result ; if 
three times, three threads, and so on until the number of 
threads are so many, and the angle so great, that we 
cease to call it a worm and begin to name it a spiral 
gear. 

It will probably occur to some minds that if glue be 
used to fasten this paper to the pattern, the moisture of 
the glue will stretch it, so as to make the ends that meet 
lap over ; this can be avoided and the ends need not be 
allowed to lap over, if a little care is exercised. Instead 
of spreading the glue over all the surface of the paper, 
put a little on the two ends that join, and also here and 
there on the surface ; then lay the paper flat and roll the 
pattern carefully on it, the pattern gathering up the 
paper around it as it is rolled. If a spiral gear is to be 
laid out this way — and it can be — the two ends of the 
paper should meet exactly. 



Fig. 108. 



Fig. 106. 




Mow to get the Lines for Thread of a ^Vorm 



(< ..^^v 




WORM WHEEL PATTERN. 



FA TTERN MAKING, 5 3 



WORM WHEELS. 

THE WAY TO GET THE ANGLE OF TEETH, AND THE MAN- 
NER OF FASTENING THEM ON. 

A WORM-WHEEL pattern is not an easy thing to make 
by any means ; it is that kind of a job on which a good 
man is apt to go astray. 

Figs. 107 and 108 represent a wheel to be made; the 
worm is shown in gear, and as I have already referred to 
it, I will confine my remarks to the wheel pattern, except 
that reference will have to be made to the angle of 
thread of worm. 

The dimensions are the first thing to be determined. 
Let the wheel be 21^" diameter, \y^" pitch, 39 teeth, 
form of tooth, involute, laid out with the aid of Prof. 
Willis' Odontograph. 

Pattern makers generally shape the thread of a worm 
pattern the same as the tooth of the gear in which it is 
to work ; but the sides of the thread should be straight, 
at an angle of 75 degrees with the axis of the worm. 
This is correct for an involute, because that is what a rack 
tooth would be, and the worm is similar to the rack in 
this case. A section of the wheel pattern is shown in 
Fig. 109 ; the rim is first built up and turned straight on 
the outside, the pattern being parted on line AB. 

A little thought will have to be exercised in building 
and turning the rim so as not to do any unnecessary 
chucking. In the first place, the face plate for turning it 



54 PATTERN MAKING, 

should be about the same diameter as the rim, so as to 
allow the ends of the teeth to be turned off. Lay each 
half up separately, with the parting joint of pattern against 
the face plate, rough off the outside and finish the inside 
of both halves, care being taken to turn the inside of both 
halves the same diameter, because of the chucking. 
This done, the rings are chucked by the inside, and, to 
do this, segments are nailed on the face plate. The out- 
side of the rim should now be finished to the size re- 
quired, and blocks for the teeth fitted on the periphery. 
These blocks should be fitted and glued on with the 
grain of the wood running at the same angle that the 
teeth are to be at the pitch line, the width of each block 
being the same as the pitch. The way to get the angle 
is shown in Fig. 110,7 representing the angle of tooth 
at the pitch line. These blocks are fastened on before 
taking the first half out of the lathe, and a groove turned 
on the joint for locating the halves concentric with one 
another. When the second half is chucked and turned 
and the blocks for teeth fixed on, as in the case of the 
first half, a projection is turned on the joint of it to fit 
the groove on the joint of the other. The two halves 
should now be put together, and the blocks for the teeth 
turned off on the ends, and finished, as seen in section 
Fig. 109. A good surface for marking out the teeth 
may be made by varnishing these blocks with yellow 
varnish. 

In Fig. 107, a part of the pattern Is shown cut through 
line AB, Fig. 109; the other part, with the three teeth 
represents the outside and ends of the teeth. To be the- 
oretically correct the teeth should be thinner on the ends 



PATTERN MAKING, 55 

than on the parting line, AB, but in practice, this is not 
generally considered, because it would make it difficult 
to draw the pattern if made that way ; the teeth in cast 
gears are therefore made the same thickness on the line 
(7 as on the pitch line D in Fig. 107. 

The Odontograph for locating a center for marking out 
the teeth is shown at E ; the instrument is nothing more 
than an angle of 75° divided off in y^" spaces on one side 
for \" in length, the y^" spaces being subdivided. Zero 
on the instrument is placed at a point on the pitch line, 
and the plain side is set to a radial line; the radius of 
the gear is then read off on the graduated side, which 
will locate a center from which to strike the tooth. In 
this case, the wheel being 2\y^" diameter, the radius is 
loy^" ; read off 1 1, which is near enough for all practi- 
cal purposes. 

To lay out the teeth on the pattern at the proper 
angle, space off half the pitch from one of the joints of 
the blocks, on the pitch line each side of the wheel. If 
these pieces for the teeth have been made to the angle of 
y, Fig, 1 10, these points on each side will be the starting 
points for dividing the teeth, and will give the angle of 
tooth. 

If the teeth are marked out also on the joint of one- 
half of the pattern, and trimmed down to the line, it will 
be an additional guide to cut the teeth by. 

The fact of the arms of the pattern being in halves 
makes them thin, and therefore weak ; but if the joints 
in the center be tongued, and the hub on each side glued 
and screwed to the arms, it will strengthen them consid- 
erably. 



56 PATTERN MAKING, 



SWEEPING STRAIGHT WINDING DRUMS. 

Fig. 1 1 1 shows one way of sweeping up hoisting 
drums. The usual way is to allow one or two fingers 
for sweeping the groove to travel the whole length of 
drum by means of a nut running on a long screw. It 
will be seen that the long screw is discarded and that 
the sweep is made the whole length that the drum is to 
be. This sweep is required to travel up and down only 
one thread, which will make a continuous thread, the 
same as if two fingers traveled the whole length by means 
of the screw. The set screws, E and F, are free from 
the spindle, so that the sweep may rise and fall as it is 
pulled around. It rises by means of a pinplate, B, bolted 
to the bottom of the sweep, and which works in a spiral 
groove cut in the hub, A ; this groove must be cut the 
same pitch that the groove of drum is intended to be. 

Figs. 1 1 2 and 1 1 3 are other views of A and B. The 
spindle is kept from turning by the set screw, H, being 
set against it; at the same time, the projection on the 
hub. A, fits into the slot G, in Fig. 112. 

After sweeping the grooved part of drum, the part C 
of the sweep may be taken off and a piece, like D, fas- 
tened to the upper cross-piece ; this is for striking the 
flange of drum and a step around the top for a guide 
by which to set the cope. While sweeping the groove 
the spindle remains stationary, but when sweeping this 




SWEEPING DRUMS. 



PATTERN MAKING, 57 

flange and step, it must revolve with the sweep ; to do 
this, the set screws, E and F, must be tightened, the pin- 
plate, B, taken off the sweep, and the set screw, H, loos- 
ened ; this will allow the spindle to revolve in its taper 
socket in the ordinary way. 

For drums over 6 ft. in diameter, it will be found 
necessary to support the top of the spindle with a tem- 
porary cross-beam, and also, to have a counterbalance 
weight to help the rising of the sweep as it is pulled 
around. 



58 PATTERN MAKING. 



MAKING WINDING DRUMS FROM PATTERNS. 

METHOD OF CUTTING THE GROOVE. 

Fig. 1 14 shows a section of a Grooved Winding Drum 
about 3 ft. diameter, and Fig. 1 1 5 shows the way pat- 
tern may be constructed. 

/^ is a 4x4'' stick ; on it three discs, A, B, C, are 
fastened and screwed by brackets. Lagging to form the 
shell is screwed around these discs, while the spider in 
the end is loose and just laid on disc A, so that it can be 
lifted with the cope. C should be made about f smaller 
in diameter than A, to allow the core, shown in Fig. 
114, to be easily lifted; this f taper on the drum will 
not be noticeable when cast, neither does it affect any- 
thing. 

Fig. 116 represents a piece of the lagging that is 
screwed on the discs, A, B, C. Fig. 1 1 7 is given to 
show how to get the proper angle of the groove; the 
distance, x, is the circumference, a the pitch, and y the 
angle that the grooves are to be cut. Fasten two pieces 
together in the form of a T square, Hke Fig. 118, for 
marking the lines on Fig. 116, and let the blade be cir- 
cular, to fit the face of the lagging. Also make a 
templet the same length and thickness of the drum, to 
mark off the grooves on the edge of lagging. 

As the outside is being rammed up, the screws that 
hold the lagging must be taken out, so as to allow A, B, 



Cast Iron h-, m 

(Ring rattern ^-y -t' *(/• lli>. 



Fig. 116 



Fig. 114. 




PATTERN FOR WINDING DRUM. 



PATTERN AM KING. 59 

C, and D to be removed after the cope is lifted. Previ- 
ous to ramming up the core, a flange, E, Fig. 114, is 
placed in the bottom of the mould ; this flange is made 
in segments and is for bolting the brake wheel to the 
drum. After the inside is rammed up and lifted out, 
this flange, E, and the lagging are drawn in and the 
groove finished off and the skin dried. 

Some may say that a pattern such as I have described 
is very costly ; in reply I would say that it would soon 
pay for itself by the difference in the cost of sweeping 
and moulding, but drums of larger diameter should be 
swept up, as they generally are. 



6o PATTERN MAKING. 



MAKING SHEAVES FROM CORE-BOXES. 

I PROPOSE to give under this head some ideas for 
making sheaves of various kinds, and will first give the 
way for making large ones from core-boxes. 

The style of sheaves, shown with cast arms, is that 
which is used to transmit power on cable car roads. The 
groove is made to receive segments that are bolted on, 
and of which more will be said further on. The right 
hand side of Fig. 120 shows one arm and a portion of 
the rim ; as will be seen, this sheave is in halves, and 
arranged for bolting together ; joint E is to be finished 
so that stock for planing must be allowed at E. In Fig. 
121 two sections are shown ; that on the right is a sec- 
tional view of the mould through the arm-core, AB, and 
that on the left through CD. These two sections repre- 
sent the mould closed, but in Fig. 1 20 I have shown the 
mould open, with the arms, F and G, set. The lower 
part of rim is made in green sand, a segment pattern 
being used to form it. This segment pattern is shown 
to the left in Fig. 120, H being a section of it. Two 
battens, a, b, are screwed on, which run to the center, 
the ends being cut to fit around the spindle. 

The lugs at the joint, for bolting the rim together, 
must be right and left hand on the segment pattern, 
using one when starting and the other when finishing. 
These lugs are screwed on temporarily. Care must be 



« 




^ 








•a 


(n 




W 


o 


X! 




O 




pq 




d ^.. 



Fig. 134* 




MAKING SHEAVES FROM CORE BOXES. 



^ FiO'i^S, 




^ig. 126. 




MAKING SHEAVES FROM CORE BOXES. 



PATTERN MAKING. 6 1 

taken to divide the arms off accurately on a level bed. 
After marking the center line on the bed for each arm, 
move the segment around on the spindle and apply the 
center line of the core print for the arm core to the center 
lines on the bed, and, as lines on sand soon disappear, 
it will be well to drive a small stake on each side of the 
print for arm core, so that, when moving the segment to 
each division, the arm print can be set down between the 
stakes, and thus insure accuracy. It is particularly nec- 
essary to divide these arms off equally, so that the bolt- 
holes shall match those in the segments that go in the 
groove, for it is the intention that all the holes, both for 
bolting together the sheave and segments, shall be cast 
in, and to compensate for any difference that may occur, 
the holes are made a little long in the rim and lugs, as 
seen aty. Fig. 120. 

Fig. 122 is the arm core-box, and I will again remind 
the pattern maker that it should be made strong, or it 
will come apart, as I have often seen, and then there is 
trouble about the cores not coming together at the cen- 
ter as they should. 

Fig. 123 shows the way some pattern makers construct 
these large arm core-boxes ; the result is, they are 
rammed apart, as shown, and then the poor core maker is 
accused of using the core-box roughly. Just as in the 
case of arm box for fly-wheels, so this box should be 
made a little longer than is necessary for the present job, 
so that the end, K, can be moved out and the arm length- 
ened for a larger wheel whenever it may be needed. 
The interchangeable pieces, i, 2, 3, form the hub. 

Fig. 1 24 is the core-box from which the cope cores, Z, 



62 PATTERN MAKING. 

in Fig. 121, are made. The same lugs,/, that are used 
on the segment pattern, can be used in this box for two 
cores, using one right hand and one left hand. The box 
is shown arranged for the first core on the left. M is 
a loose piece half the width of the core print that receives 
the arm core. It will be seen that this box is made 
longer than the core is needed. This is to enable us to 
change ends with the loose piece, M, when making a 
core the opposite hand. The length of this box is from 
the center of the arm to the joint E, but the \" stock, 
which is allowed for planing the joint at E, makes the 
box \" longer than the eighth part of the half sheave, 
and therefore \" too long for the other cores, so that a 
\" piece must be put in the end of the box after making 
two cores with the lug,y. 

Fig. 125 is the box for the groove cores. The section 
of this box shows it arranged for making the cores in 
two parts, to be pasted together at 0, Fig. 121. The 
cope part of this core is a little different from the bottom 
part; a loose piece, g, in Fig. 125, is fitted in the bottom 
of the box, to be left in for the bottom part of core and 
taken out for the cope part. The groove that this core 
is to form is turned on the two sides, but not in the bot- 
tom ; tool clearance should therefore be allowed on each 
side in the bottom to accommodate the turning. This 
is seen in the section at N. 

I have not shown any core-box for the slab core, /, as 
it is nothing but a plain core, and the box is simple and 
needs no explanation as to making it. 

Fig. 126 is the core-box for the hub. It Is made the 
depth of P, in Fig. 121. This view gives all the explan- 




Fig. 129 

MAKING SHEAVES FROM CORE BOXES. 



/ 

PATTERN MAKING. 6^ 

ation that is necessary as to the way to make it. The 
faces, £, of the hub and lugs are covered with slab cores. 

Another type of sheaves is shown in Fig. 127. This 
style can be made considerably cheaper than those I 
have already described. Dispensing with the groove 
that receives the segments makes it very simple to 
mould, and also easier for turning the periphery of cast- 
ing. The plan for forming the arms and the hub is the 
same here as in Fig. 120. The segment pattern for 
making the green sand part of mould is seen in Fig. 128, 
of which Fig. 129 is an end view. The pieces that run 
to the center are not screwed on top of segment in the 
usual way, but on the step that is made in the segment 
at a, Fig. 129. By making it in this way, a large part 
of the rim can be made in green sand, as shown in Fig. 
130. 

The core-box for core A, Is made in very much the 
same way as in Fig. 124. The segment that is bolted 
on the periphery of this sheave is moulded edgewise; 
there are chipping strips on the inside at d, c, d, e, Fig. 
131 ; on the side,/", stock for planing is allowed, so that 
the segment may set straight against the flange of the 
wheel. 

I once had a little experience with some of these seg- 
ments. When the first lot of those in Fig. 1 3 1 were 
being fitted on the wheel, it was found they had straight- 
ened somewhat, just as represented by the dotted lines; 
it was evident that these segments straightened in cool- 
ing, the two thin flanges, ^ :r, cooling first and pulling the 
casting out of its true circle ; in the next, I took care to 
allow for this w-hen making the pattern. 



64 PATTERN MAKING, 

When there is a number of these sheaves to make, 
instead of closing the top with slab cores, as I have 
shown, it would pay to make a cast iron half ring with 
which to cover the top. This half ring should have a 
number of spikes on one side, and on it a thick coat of 
loam, struck off level, dried, and blacked. 



Fly, 133. 




Fig. 135. 



MAKING SHEAVES FROM PATTERNS. 



PATTERN MAKING. 6$ 



MAKING SHEAVES FROM PATTERNS. 

There is not much scheming required to make a pat- 
tern for a sheave, such as shown in Fig. 132, and yet, to 
show the way it should be made, may not be entirely 
out of place here, as I want to bring in a few points that 
have not hitherto been considered. 

I have said that into the groove of this style of sheave 
are bolted segments that take the cable. The advantage 
of this arrangement is evident, as it allows the segments 
to be renewed when worn out. I have shown in Fig. 
132 a part of the rim and a cross-section of the sheave; 
this shows the manner of bolting the segments to the 
sheave. The groove, into which the segments are bolted, 
is to be turned, but the groove of the segment is left 
rough. 

Chipping pieces are cast on each side of the segment, 
as seen at a, b, c, d, Fig. 133, because it is intended that 
the segment shall not bear in the bottom of the groove, 
but only on the chipping pieces by the sides, and a,t e e; 
see cross-section, Fig. 132. 

Fig. 133 shows the pattern of the segment, and is 
made to be moulded on the edge, the groove being in 
the cope ; it is desired to cast the bolt-holes, and care 
must be taken in spacing them off, because they are 
wanted to match those in the sheave, which are also cast 
in. I have marked the core prints for these holes ; the 
bottom print is made something like the cope print — 



66 PATTERN MAKING. 

oblong — as shown at/; this is done in order that the 
core may stand in the mould more securely while the 
cope is being closed. If a round print were used just 
the size of holes, the cores would be top-heavy and diffi- 
cult to locate in the mould, hence the necessity of mak- 
ing the bottom print as shown. The core-box for this 
bolt-hole should be made as shown in Fig. 1 34. 

It is understood that these sheaves are bolted together 
in halves, so that in making a pattern, only one-half will 
be required. Proceed by building up and turning a 
whole ring, of which Fig. 135 shall be the section; A is 
the print for carrying the groove cores. After turning 
the ring, cut a stick the exact length of the inside diam- 
eter — this will be a gauge to see whether the ring has 
sprung after being cut in two, and, if it has, to bring it 
back to the gauge when fastening in the arms. After 
sawing the ring in two, glue and screw it together 
strongly, as seen in Fig. 136; but before doing so, it 
must be remembered, as before, that stock for planing 
must be allowed at the joints where the ring is bolted 
together, so that the pattern shall be \'' over the half cir- 
cle. In order that this may be, the ring should not be 
cut exactly in halves, but \" one side of the center, mak- 
ing one part about \" short, not reckoning anything for 
saw cut — with saw cut would probably be \" short. 
Now, if after sawing the ring, two of the ends be brought 
together, it will only be necessary to build on one end of 
one of the sections. Having done this, the ring is ready 
to have the arms fitted in, which should be done by 
letting them in the rim, as represented by dotted lines at 
A B, Fig. 132. 



. PATTERN MAKING. 67 

Care must be taken not to fit the arms in so tightly as 
to spring the ring out of round ; this can be very easily 
done. After locating the arms, bore two ^" holes from 
the outside of ring into each arm, and glue in hard wood 
dowel pins ; this will make a strong job. The small 
bosses, of which one is shown at C, Fig. 132, are turned 
and sawed Oiit with a narrow band-saw to fit over the 
rim. This is done by inserting each boss in a block 
with a hole through it the size of the boss ; two views of 
this block are seen in Fig. 137. The boss is fixed in 
the hole D, and sawed to the shape of the inner part of 
rim. Of course, the block is fitted over the rim first, to 
act as a guide for sawing them out. 

The core-box for the groove need not be made with 
loose piece in the bottom, as in case of forming these 
sheaves with cores, because the cope closes down on top 
of print, and not on the dotted line. Fig. 1 36. 



68 PATTERN MAKING, 



SHEAVES WITH WROUGHT IRON ARMS. 

AN ORIGINAL WAY OF MAKING THE HUB. 

The style of sheave shown in Fig. 138 is used exten- 
sively in mines for carrying rope; the arms, which 
spread on either side, act like stay-rods to the rim, 
making it very rigid sidewise, at the same time forming 
altogether, a light, but strong, sheave. 

To the left of Fig. 138 is shown a section of the rim 
with wrought iron arms cast into it ; to the right, a sec- 
tion of the cores which form the rim ; and at the center, a 
section of the cores forming the hub. 

The lower part of the mould is formed with green 
sand, the segment shown in Fig. 139 being swung 
around from the center, C. The cope is formed with 
cores made from box shown in Fig. 140. Fig. 141 is a 
cross-section of this box. 

While this is a good way to make sheaves of large 
diameters, for those under 8 ft. diameter a full ring 
is probably a better way, providing the ring can be 
stored so as to lie flat on its side, instead of standing on 
its edge ; for, having no arms, a large ring standing edge- 
wise would soon become oval. 

The cores forming the groove are made in halves 
from the box, of which Figs. 142 and 143 are two views; 
these cores are pasted together at the joint, A, Fig. 138. 
Four round cores are made to form the hub ; these are 



Fia- 13 S. 



Sand ■''■:: 



FiU' l^C 




Fig. 143. 



m 



Cleat 



SHEAVEiS WITH WROUGHT IRON ARMS. 



PATTERN MAKING, 6g 

set one on top of the other after making the lower part 
of the mound with the segment. The lower hub core, 
B, through which there is a hole, should be set over the 
pin from which the segment has been swung around. 
This will locate the hub concentric with the rim. Half 
of the arms should now be set in the mould, after which, 
the two middle cores, C and D, are located. When C 
and £> are being pasted together at the joint, £, care 
should be taken to get the holes that receive the arms 
exactly midway between those in the lower part. The 
center core, F, should now be set, then the balance of 
the arms and the top core, G. When pouring these 
sheaves, the rim is allowed to shrink all it will before 
pouring the hub, and in large ones, the hub is not 
poured until the following day. 

Figs. 144 and 145 are sections of the round core- 
boxes for the hub cores, CD and DG. Plenty of draught 
should be made on the inside of these two boxes at a a; 
the half round prints for the arms are shown at d b. 

The small bosses shown in Figs. 146 and 147 are used 
in cope core-box, Fig. 140; the prints on these small 
arm bosses vary ; the cores which cover those arms run- 
ning upward from the hub, should have Fig. 146 in the 
box, and those which run downward, Fig. 147. The 
bosses on the segment are made similar. 



70 PATTERN MAKING. 



A MACHINE 

FOR 

SWEEPING CONICAL DRUMS. 

DESIGNED BY THE AUTHOR. 

It may not be understood by some why a winding 
drum is sometimes made conical instead of a straight 
cylindrical form, and it may not be entirely out of place 
here to explain the reason, for the benefit of such. 

Conical drums are used for winding heavy loads from 
deep mines. When the skip or load is at the bottom of 
the mine, ready to be hauled up, the winding on the 
drum begins at the small end, and, as the rope does not 
wind as fast on the small end as it does on the large end 
of the drum, it allows the slack rope in the shaft to be 
gradually taken up at the starting, and also prevents the 
load from starting too suddenly. The engines also gain 
a decided advantage when winding with conical drums, 
because, instead of the winding being started at full 
speed, it gradually increases, thus giving the engines a 
better chance to do their work. 

It is scarcely necessary to inform my readers that it 
requires a great deal more skill to build and properly 
secure a mould for a large conical drum than it does to 
mould a grate bar ; but there is a class that stands so 
high in the engineering profession, that to them all foun- 



Fig. 148 




SWEEPING CONICAL DRUMS. 



PATTERN MAKING. 



71 



dry work is just a little above unskilled labor — something 
requiring more brute force than anything else. Such 
ideas, though, do not prevail among our genuine and 
practical engineers ; they are only found among the clev- 
erly ignorant. 

All those who have much to do with the machinery 
business know what an amount of consultation and 
scheming is necessary before some jobs in a foundry can 
be started, and then how it requires men of good sound 
judgment to execute the work. 

The building of a mould for a large conical drum is 
one of these jobs. The way of sweeping the groove, an 
arrangement for which I propose to describe, is only a 
small item of the work. 

In Fig. 148, A is the sweep that travels up and down 
the screw, B, as it is pulled around. The spindle, C, is 
secured to the cross, D, at the bottom ; the bevel gear is 
fast on the spindle, two set-screws in the hub holding it 
in place ; the bracket, E, is loose, and turns on the spin- 
dle ; it has a bearing at a, in which the pinion shaft runs ; 
the end of this shaft is carried by a tee piece that turns 
on the spindle. The pinion shaft and the screw are con- 
nected by a universal joint, while the screw is carried by 
two adjustable curved pieces, F and G. Guide-rod, H, 
keeps the nut from turning on screw, B ; arm, /, fits over 
the bracket, E, and carries the curved piece, F\ this arm 
is also adjustable. 

Now, it will be clearly seen that, if the arm, J, and the 
bracket, E, are pulled around, it will cause the pinion and 
the screw, B, to turn, thus making the sweep. A, to travel 
a certain distance every time it goes around. The gears 



72 PATTERN MAKING, 

determine the pitch of the groove to be swept; if the 
proportion of the gears are three to one, and the screw 
\" pitch, then the sweep will travel \\" at every turn, 
making a groove ij'^ pitch. When any other pitch is 
required, the gears must be changed for those of a differ- 
ent proportion, for instance, for a 2" pitch drum the pro- 
portion of the gears would be 4 to i. Bracket, E, is 
made so as to permit the use of gears of different sizes. 

When a drum is wanted with a left-hand groove, the 
gear on the spindle is turned upside down, and located 
under the pinion instead of over it. The machine is also 
arranged so that a drum of any angle can be swept. 
This is done by loosening the bolt that holds part F in 
place, and by taking out those in the upper part, G, thus 
allowing the screw to be swung at any angle from the 
center of the universal joint. 

The reason for making the arm, /, separate from the 
bracket, E, is obvious ; it is to give a better chance for 
adjusting the lower part of the machine than the swing- 
ing of the screw gives. The pinion shaft runs in close 
to the upright spindle, so that when the set-screw in the 
pinion is loosened, the shaft can be pulled out to the 
required distance, and the set-screw in pinion be tight- 
ened again. When this is done, it will be found necess- 
ary to bolt on the flanged sleeve, K, to the end of 
bracket, E, between the universal joint and the bearing, a. 
For building and sweeping up the mould roughly, the 
screw and pinion shaft can be disconnected entirely and 
a plain sweep made, bolting it to the upper and lower 
arms, y and /. 

The engraving only represents the model which I 



PATTERN MAKING. 73 

made of this machine ; the details of the machine proper 
will vary somewhat. For instance, where there are solid 
boxes on the bracket, E, for the spindle and pinion shaft, 
there should be caps, so as to make it easier to discon- 
nect the parts. The universal joint should also be made 
separate from the screw and pinion shaft; many other 
items would need changing when building a machine to 
do the work. 



74 PATTERN MAKING, 



GEAR TEETH. 

In the following pages there are a number of teeth 
laid out, full size, from one inch pitch to three inch, ad- 
vancing by quarter-inches. 

There are fourteen separate teeth in each pitch, suit- 
able for gears having from fourteen to eight hundred 
teeth; they have been laid out from Prof Robinson's 
Templet Odontograph and are interchangeable. The 
clearance allowed between the teeth is 2V of the pitch, or 
in other words, the space is jVo a-i^d the thickness of tooth 
iVo of the pitch ; the height of the tooth is f of the pitch, 
and the distance from pitch line to top tVo of the pitch. 
This is the proportion used for general purposes. 

A templet can be made from any of these teeth and 
fastened on a rod and used in the same way as the 
Odontograph is in Fig. 96. It would be impossible in a 
book of this kind to give the profiles of gear teeth which 
would serve all cases, so that I have confined myself to 
the system that is generally adopted and known as the 
Interchangeable System, that is, all spur gears of the 
same pitch made under this system will run together. 
For special gearing and bevel gears other settings are 
preferred ; those which I have taken are on each tooth, 
the setting for the flank being marked on the inside of 
pitch line and that for the face on the outside. The 
thickness of each tooth at the bottom and top, and also 



PATTERN MAKING. 75 

at the pitch line, is correct, so that by the aid of the set- 
tings marked, the odontograph can be easily applied for 
striking the curves on a piece of sheet zinc, from which 
a templet tooth is usually made. 

The numbers show how many different size wheels can 
be made with same size tooth ; for instance — \2 to 47 
means that the same shape tooth will answer for gears 
which are to have from 42 to 47 teeth. 

On suceeding pages, at the end of the book, will be 
found plates, in which some of the teeth are shown in 
gear, together with the way they should be made. 



Table of 


//^^ 


Diameter of Wheels at the Pitch Circle, from 


7/ /^ j>oo 71'<r//^ 




Pitch of the Teeth. 




inch. 1 


in 


ch. 


inches. 1 


inches. I 


inches. 


inches. | 


inches. 


inches. | 


inches. 


inches. 




I 


)4- 


I 


%■ 




2 


2 


Ys- 


2I4. 


2 


^■ 


2%. 




3- 


3M- 


33^. 


II 





6|- 





6f 





7 





7* 


7¥ 





8| 


9| 





io| 





III 


I o\ 


12 





6| 





7i 





7f 





8i 


8| 





9f 


io| 





lU 




of 


I If 


13 





7f 





7i 





8| 





8| 


9l 





lOf 


iij 




o| 




i| 


I 2j 


14 





7i 





H 





9 





9^ 


10 





Hi 


I of 




Ij 




2| 


I 3l 


15 





8^ 





9 





9f 





loi 


lof 







I li 




2f 




3i 


I 4l 


16 





9 





9l 





loi 





I of 


11^ 




o| 


I 2 




3l 




4J 


I 5i 


17 





9l 





loi 





io| 





lU 


I oi 




I^ 


I 2| 




4i 




5i 


I 6i 


18 





10 





io| 





iij 




oi 


I oi 




2| 


I 3l 




5i 




6f 


I 8 


19 





io| 





III 




0^ 




o| 


I if 




3J 


I 4f 




6i 




7f 


I 9h 


20 





"i 









of 




II 


T Q.^ 




4 


I 5^ 




7l 




8| 


I lol- 


21 





ii| 




0^ 




I^ 




2i 


I 3 




4f 


I 6| 




8^ 




9l 


I iif 


22 




of 




u 




2 




2i 


I 3l 




5i 


I 7\ 




9 




I of 


2 o| 


23 




o| 




If 




2f 




3l 


I 4^ 




6| 


I 8 




10 




ii| 


2 l| 


24 




I^ 




2f 




3f 




4i 


I 5i 




7J 


I 9 




lOf 


2 


o| 


2 2| 


25 




2 




2i 




3l 




4l 


I 6 




8 


I 9I 




III 


2 


II 


2 3I 


26 




2i 




3i 




4j 




5^ 


I 6| 




8| 


I io| 


2 


oi 


2 


2| 


2 4|- 


27 




3 




4^ 




5i 




61 


I 7f 




9l 


I iif 


2 


II 


2 


3l 


2 6J 


28 




3l 




4l 




51 




6| 


I 8 




10^ 


2 Oo^ 


2 


2| 


2 


4l 


2 7i 


29 




4^ 




51 




6| 




7l 


I 8i 




Hi 


2 l| 


2 


34 


2 


6 


2 8f 


30 




4i 




6 




7J 




^ 


I 9J 


2 





2 2} 


2 


4f 


2 


7 


2 9l 


31 




5f 




6J 




/4 




9 


I loi 


2 


o| 


2 3i 


2 


5f 


2 


8 


2 10^ 


Z'^ 




51 




7^ 




8f 




98 


I II 


2 


li 


2 4 


2 


6h 


2 


9l 


2 iif 


33 




6| 




71 




9 




lof 


I iif 


2 


2i 


2 4I 


2 


7I 


2 


loj 


3 o| 


34 




7 




8| 




9f 




II 


2 of 


2 


3 


2 51 


2 


8^ 


2 


Hi 


3 If 


35 




7i 




9 




lol 




III 


2 I 


2 


3t 


2 6| 


2 


9t 


3 


oi 


3 3^ 


36 




8 




9^ 




10|)2 


o| 


2 2 


2 


4f 


2 7? 


2 


I of 


3 


li 


3 4i 


37 




8f 




10 




11^ 


2 


I 


2 2j 


2 


5* 


2 8| 


2 


III 


3 


2i 


3 5i 


38 




9i 




io| 


2 


oi 


2 


If 


2 3i 


2 


6i 


2 9V 


3 


o\ 


3 


38 


3 6f 


39 




9f 




III 


2 


of 


2 


2f 


2 4 


2 


7 


2 10^ 


3 


ik 


3 


4l 


3 7f 


40 




lOf 




11^ 


2 


I^ 


2 


3 


2 4l 


2 


7l 


2 I0| 


3 


2\ 


3 


5l 


3 8^ 


41 




loj 


2 


02^ 


2 


2j 


2 


3l 


2 51 


2 


8f 


2 Iif 


3 


3f 


3 


"8 


3 9f 


42 




iij 


2 


I 


2 


2| 


2 


4* 


2 6 


2 


9f 


3 o| 


3 


4^ 


3 


78 


3 io| 


43 


2 





2 


If 


2 


-,3 

38 


2 


5 


2 6| 


2 


loi 


3 If 


3 


5 


3 


8| 


4 


44 


2 


oj 


2 


2} 


2 


4 


2 


i)4 


2 7^ 


2 


II 


3- 2j 


3 


6 


3 


9^ 


4 I 


45 


2 


I 


2 


H 


2 


4l 


2 


6^ 


2 8i 


2 


III 


3 3I 


3 


7, 


3 


10^ 


4 2^ 


46 


2 


if 


2 


3^ 


2 


5i 


2 


7I 


2 9 


3 


of 


3 4i 


3 


7f 


3 


in 


4 3\ 


47 


2 


II 


2 


4 


2 


6 


2 


71 


2 9l 


3 


ij 


3 5l 


3 


8i 


4 


of 


4 4I 


48 


2 


2| 


2 


4| 


2 


6J 


2 


^ 


2 lOf 


3 


2i 


3 6 


3 


9f 


4 


if 


4 5^ 


49 


2 


3f 


2 


5i 


2 


7i 


2 


9h 


2 II 


3 


3 


3 61 


3 


io| 


4 


2f 


4 6J 


50 


2 


3l 


2 


5¥ 


2 


71 


2 


9l 


2 Ilf 


3 


3l 


3 7l 


3 


III 


4 


3l 


4 7l 


51 


2 


4* 


2 


6* 


2 


8* 


2 


10^ 


3 oh 


3 


4i 


3 8f 


4 


o| 


4 


4l 


4 8| 


52 


2 


4i 


2 


7i 


2 


9i 


2 


i4 


3 li 


3 


5l 


3 9? 


4 


if 


4 


5l 


4 10 


53 


2 


51 


2 


7f 


2 


9l 


2 


III 


3 2. 


3 


61 


3 lo? 


4 


2f 


4 


6i 


4 II 


54 


2 


6 


2 


8i 


2 


lof 


3 


0^ 


3 2| 


3 


7 


3 II 


4 


3i 


4 


7i 


5 ol 


55 


2 


6f 


2 


8| 


2 


II 


3 


li 


3 3f 


3 


71 


4 0^ 


4 


4i 


4 


8| 


5 li 


56 


2 


7i 


2 


9f 


2 


III 


3 


H 


3 4J 


3 


8i 


4 I 


4 


5* 


4 


9i 


5 2| 


57 


2 


71 


2 


10 


3 


oi 


3 


2j 


3 4¥ 


3 


9f 


4 Jl 


4 


6| 


4 


io| 


5 3^ 



76 



Table of the Diameter of Wheels at the Pitch Circle — Continued. 



Pitch of the T6eth. 




9 6| 

9 7l 



Table of the Diameter of Wheels at the Pitch Circle — Continued. 

Pitch of the Teeth. 



inch. 

T3/r 



105 
106 
107 
108 
109 
no 
III 
112 

114 

115 

116 

117 

II 

119 

120 

121 

122 

123 

124 

125 
126 
127 
128 
129 
130 

131 

132 

133 

134 

135 

136 

137 
138 

139 
140 

141 

142 

143 
144 

115 
146 

147 
148 
149 
150 



102 
II 

III 

o| 
li 

l8- 

3 
-.1 

51 

4 

4t 

51 

51 

61 

6| 

7l 
8 

8| 
9 

9I 
loj 

loi 
III 

lU 

of 
I 

I'J 

2 

2| 

3^ 
35- 
4l 
4l 

51 

6 

6.^ 



71 
81 
8| 
9i 
9i 

10.^ 

II 

III 



inch. 



2a 
2| 

3* 
4^ 
4l 
5i 

5l 
6^ 

7 

7t 

8i 

8| 

9J 



5 10 
5 lot 
5 III 

5 iif 

6 oj 
6 I 
6 il 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 



2f 

38 



4l 

5l 

5l 

61 

7 

7* 

81 

81 

9i 



inches. 



6 10 
6 \o\ 
6 iii 



ii4 

oi 

2 

28 

3t 
3« 
4^ 
5 



6| 

71 



9t 



o. 
I 
^■^ 

'^ ^ 
2 



5 10 
5 lof 

5 Hi 

6 o 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 



1 

■4 
• 3 

■4 

5| 
3l 
3l 
4l 
5 

51 
61 
7 

7i 
81 
8| 
9l 



6 10^ 

6 io| 

6 III 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 



o| 

II 
2 

2| 

3l 
3l 
4l 
5^ 

i)4 
O4 



inches. 

2U. 



inches. 



81 

9 

9\ 



7 lol 
7 lo^ 
7 iij 



5 II 



6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 

6 lOj 
6 "i 
6 III 
oi 



of 
I 

^4 

-^8 

3 
3l 

4| 
5i 
51 
6.^ 

ll 
71 
8i 

9^ 
9l 



II 



2^ 

31 

4 

4| 

5i 

6 

6| 
71 
8 

8f 
91 
7 10 

7 lof 

7 iif 

8 o 
8 oj 
8 If 
8 2 

8 2| 

8 3l 

8 4^ 

8 Ai 

8 5] 



3 

3l 
4l 
5 

^4 

6.^ 

7i 



6 

6 

6 

6 

6 

6 

6 

6 

6 8| 

6 9l 

6 10 

6 io| 

6 ii| 

7 

7 

7 

7 

7 



inches. 



I 

T 5 

2^ 
^4 

3 



3l 
4j 

5^ 
6 

61 



7 
7 
7 
7 
7 

7 71 
7 8 
7 8| 
7 9j 
7 loi 
7 io| 

7 lU 

8 oj 
8 I 



8 3l 

8 3l 

8 4^ 

8 51 

8 6 



63 
"4 



8 7J 



8 9^ 
8 loi 
8 II 



6 ii.J 



ol 
2 

^4 

3l 
4l 

5^ 
6 

6| 
7l 
81 
9l 



7 
7 
7 
7 
7 
7 
7 
7 
7 
7 
7 
7 
7 10 

7 io| 

7 iit 

8 ol 
8 I 
8 U 
8 2| 
8 3l 
8 4l 
8 5 
8 5l 
8 6| 
8 7* 
8 81 
8 9 
8 9I 
8 io| 
8 III 



ol 



l3 

*4 
2f 

31 
41 
5 
51 



incnes. 
2%. 



7 7-8 
7 83 

7 9l 
7 lol 

7 Hi 

8 o^ 

8 ij 
8 2 



8 3f 

8 4l 

8 51 

8 61 

8 71 
8 8i 

8 9 

8 9i 
8 io3 

8 III 
0.1 



9 

9 

9 

9 

9 

9 

9 

9 

9 

9 

9 . 

9 los 

9 II 
10 o 
10 
10 
10 
10 
10 4I 



oi 

li 
2^ 

3I 



10 
10 



78 



9 


7i 


10 


6i 


9 


8i 


10 


rk 


9 


9 


10 


^i 


9 


9i 


10 


9\ 


9 


lO.i 


10 


lo-J 


9 


III 


10 


III 



inches. 

3- 



8 4l 
8 5^ 
8 61 

8 7^ 
8 8 
8 9 
8 10 
8 io| 
8 III 

03 



I4 
23 

3i 
4i 

51 
6| 

n 

8^ 

9l 

9 io| 

9 III 

o ol 

o II 



o 3J 
o 4l 



o 5 
o 6 

o 7 



o 81 
o 9I 
o io| 

O Ilf 

of 

If 

2o 

3? 
4I 

5l 
6^ 

7I 

8] 

9l 

lol 



inches. 

3%- 



O^ 

I^ 

^8 

^8 

3l 

44^ 

51 
6| 
7i 
81 
9 s 

9 lOs 

o o 

o 

o 

o 

o 

o 

o 

o 

o 

o 

o 10 

o Hi 

ol 

ll 

2!> 

3l 
4l 
5i 
6^ 
7l 
8^ 
9] 
lof 
11^ 
o| 

I^ 

2^ 
3I 

4i 
6 

7 



I 

2 

3^ 
4^ 
5J 
6] 
71 

^5 
9? 



9* 
2 loj. 
2 II 



inches. 



9 8| 
9 10 

9 "1 

o o| 

o ll 

O 2% 

o 3l 
o 43 

o 6 

o 7 
o 8^ 
o 9I- 
o 10^ 

O II| 

oh 

I5 



23- 
^4 

3 1 

5 

6^ 

n 

8| 

9l 
10^ 

ii| 

2 



A\ 
51 
2 6| 

2 7 T 

2 8^ 
2 9| 

2 10; 

3 o 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 



I 

2I 

4| 
5^ 
6^ 
71 

10 
111 



Table 


of the Diameter of Wheels at the Pitch Circle 


— Continued. 












Pitch of the Teeth. 








Number of 
Teeth. 






















inches. 


inches. 


inches. 


inches. 


inches. 


inches. 




2l^. 


2^. 


2%. 


; 


S- 


3^4- 


3y2- 


151 


9 


0^ 


10 


0^ 


II oj 


12 


0^ 


13 


0^ 


14 o\ 


152 


9 


0^ 


10 


ol 


II I 


12 


I| 


13 


i\ 


14 If 


153 


9 


If 


10 


If 


II I^ 


12 


2 


13 


2\ 


14 2f 


154 


9 


2} 


10 


2h 


II 2| 


12 


3 


13 


3f 


14 3i 


155 


9 


3 


10 


3f 


II 3l 


12 


4 


13 


4f 


14 4f 


156 


9 


?>% 


10 


4^ 


II 4^ 


12 


4l 


13 


51 


14 51 


157 


9 


4| 


10 


4l 


II 5I 


12 


5-8- 


13 


6f 


14 6i 


158 


9 


51 


10 


5f 


II 6| 


12 


6| 


13 


7f 


14 8 


159 


9 


Si 


10 


6^ 


II 7i 


12 


7l 


13 


8f 


14 9i 


160 


9 


6| 


10 


7f 


II 8 


12 


8| 


13 


9i 


14 lol 


161 


9 


7f 


10 


H 


II 8| 


12 


9l 


13 


10^ 


14 iif 


162 


9 


8 


10 


Si 


II 9I 


12 


io| 


13 


III 


15 of 


163 


9 


8| 


10 


91 


II lof 


12 


III 


14 


o| 


15 ij 


164 


9 


9l 


10 


io| 


II 11^ 


13 


o| 


14 


If 


15 2t 


165 


9 


IO| 


10 


iif 


12 o| 


13 


4 


14 


2| 


15 3l 


166 


9 


\ol 


II 





12 ij 


13 


2h 


14 


3l 


15 4l 


167 


9 


iif 


II 


0^ 


12 2I 


13 


3l 


14 


4l 


15 6 


168 


10 


"8 


II 


i| 


12 3 


13 


4l 


14 


51 


15 7i 


169 


lo 


I 


II 


^8 


12 3i 


13 


51 


14 


6| 


15 8i 


170 


lo 


I| 


II 


3i 


12 4I 


13 


6f 


14 


7l 


15 9f 


171 


lO 


2| 


II 


4 


12 5f 


13 


7i 


14 


H 


15 loi 


172 


10 


Z\ 


II 


4l 


12 6^ 


13 


8^ 


14 


9i 


15 iif 


173 


10 


3i 


II 


51 


12 78 


13 


9* 


14 


lOi 


16 of 


174 


10 


4^ 


II 


6| 


12 8} 


13 


loi 


15 





16 II 


1/5 


10 


5l 


II 


7i 


12 9I 


13 


la 


15 


li 


16 2i 


176 


10 


6 


II 


8 


12 10 


14 





15 


2| 


16 4 


177 


10 


6| 


II 


H 


12 I0| 


14 


I 


15 


3* 


16 5i 


178 


10 


7l 


II 


9f 


12 III 


14 


I5 


15 


4i 


16 6f 


179 


10 


8^ 


II 


lOf 


13 of 


14 


2i 


15 


5l 


16 7f 


i3o 


lO 


8J 


II 


III 


13 IJ 


14 


35 


15 


6i 


16 8^ 


181 


10 


9l 


12 





13 2f 


14 


4i 


15 


7\ 


16 9f 


182 


10 


lot 


12 


oi 


13 3i 


14 


5l 


15 


81 


16 io| 


1S3 


10 


II 


12 


If 


13 4J 


14 


6| 


15 


9i 


16 ni 


184 


10 


iif 


12 


2f 


13 5 


14 


7f 


15 


lof 


17 o| 


185 


II 


of 


12 


31 


13 5i 


14 


8f 


15 


iif 


17 2^ 


186 


II 


i| 


12 


4 


13 6^ 


14 


9I 


16 


of 


17 3l 


187 


II 


i| 


12 


4i 


13 7l 


14 


lOo^ 


16 


If 


17 4f 


188 


II 


2| 


12 


5h 


13 8i 


14 


llh 


16 


2| 


17 5l 


1 89 


II 


3l 


12 


6| 


13 9f 


15 


o| 


16 


3i 


17 6^ 


190 


II 


4 


12 


7i 


13 io| 


15 


if 


16 


4i 


17 7f 


191 


II 


4| 


12 


71 


13 11^ 


15 


2f 


16 


5h 


17 8| 


192 


II 


5J 


12 


8f 


14 


15 


3i 


16 


6| 


17 9i 


193 


II 


6^ 


12 


9i 


14 o| 


15 


4\ 


16 


7l 


17 II 


104 


II 


6.^ 


12 


io| 


14 i| 


15 


5\ 


16 


8f 


18 0^ 


1.5 


II 


7i 

• 


12 


11^ 


14 2| 


15 


6^ 


16 


9l 


18 il 



79 



Table of the Diameter of Wheels at the Pitch Circle — Continued. 



^O 









Pitch of the Teeth. 










N^umbcr of" 


















Teeth. 


inches. 


inches. 


inches. 


inches. 


inches. 


linches. 




2l^. 


^'A- 


2%. 


3- 


3K- 


3>^. 


196 


II 8f 


12 ii| 


14 3? 


15 7l 


i6 


lOf 


18 


2f 


197 


II 9 


13 o| 


14 4l 


15 H 


16 


III 


18 


3l 


198 


II 9l 


13 ij 


14 5l 


15 9 


17 


o| 


18 


4i 


199 


II loh 


13 2| 


14 6J 


15 10 


17 


If 


18 


51 


200 


II ii| 


13 3i 


14 7 


15 io| 


17 


2| 


18 


6| 


201 


II III 


13 3l 


14 7l 


15 III 


17 


3l 


18 


71 


202 


12 of 


13 4l 


14 8| 


16 ol 


17 


4l 


18 


9 


203 


12 if 


13 5t 


14 98 


16 II 


17 


6 


18 


10 


204 


12 2 


13 6i 


14 loj 


16 2f 


17 


7 


18 


III 


205 


12 2| 


13 7l 


14 iif 


16 3l 


17 


8 


19 


oi 


206 


12 3i 


13 7l 


15 of 


16 4f 


17 


9l 


19 


If 


207 


12 4} 


13 8| 


15 I* 


16 5l 


17 


io| 


19 


2^ 


208 


12 4| 


13 9I 


15 2 


16 6| 


17 


III 


19 


3f 


209 


12 5t 


13 lol 


15 2| 


16 7^ 


18 


o\ 


19 


4| 


210 


12 6f 


13 iiJ 


15 3I 


16 8^ 


18 


I] 


19 


51 


211 


12 7^ 


13 III 


15 4l 


16 9I 


18 


2\ 


19 


7 


212 


12 7l 


14 of 


15 5^ 


16 lof 


18 


3l 


19 


8| 


213 


12 8^ 


14 If 


15 6| 


16 iif 


18 


4l 


19 


9l 


214 


12 9I 


14 2^ 


15 7l 


17 of 


18 


5i 


19 


lof 


215 


12 9I 


14 3 


15 81 


17 i| 


18 


6| 


19 


iij 


216 


12 lof 


14 3I 


15 9, 


17 2\ 


18 


7f 


20 


o| 


217 


12 Ilf 


14 4I 


15 9I 


17 3I 


18 


81 


20 


If 


218 


13 


14 5l 


15 io| 


17 4I 


18 


9^ 


20 


2| 


219 


13 o| 


14 e\ 


15 III 


17 58 


18 


10^ 


20 


4 


220 


13 IJ 


14 7 


16 o| 


17 6 


18 


III 


20 


5^ 


221 


13 2\ 


14 7I 


16 if 


17 7 


19 


of 


20 


64^ 


222 


13 2| 


14 8| 


16 2f 


17 7l 


19 


If 


20 


7l 


223 


13 3f 


14 9t 


16 3^ 


17 8f 


19 


2| 


20 


^ 


224 


13 4i 


14 loi 


16 4 


17 9l 


19 


3l 


20 


98 


225 


13 si 


14 II 


16 4I 


17 loi 


19 


4l 


20 


io| 


226 


13 5I 


14 III 


16 5I 


17 ii| 


19 


5l 


20 


III 


227 


13 6i 


15 oi 


16 6| 


18 o| 


19 


61 


21 


o| 


228 


13 7i 


15 it 


16 7i 


18 If 


19 


7l 


21 


2 


229 


'3 ^ 


15 2^ 


16 8f 


18 2f 


19 


81 


21 


3l 


230 


13 8| 


15 3 


16 9I 


18 3l 


19 


9l 


21 


4i 


231 


13 9i 


15 Zi 


16 io| 


18 4^ 


19 


io| 


21 


5f 


232 


13 10^ 


15 4f 


16 II 


18 5^ 


20 





21 


6f 


233 


13 io| 


15 5i 


16 III 


18 6| 


20 


I 


21 


7^ 


234 


13 "2 


15 6^ 


17 o| 


18 71 


20 


2 


21 


8| 


235 


14 o\ 


15 7 


17 if 


18 8f 


20 


3 


21 


9l 


236 


14 I 


15 7l 


17 2* 


18 9l 


20 


4^ 


21 


io| 


237 


14 i| 


15 H 


17 3i 


18 lof 


20 


5^ 


22 





238 


14 2| 


15 9I 


17 4I 


18 III 


20 


6i 


22 


a 


239 


14 3l 


15 10^ 


17 5^ 


19 o| 


20 


7^- 


22 


2j 


240 


14 3l 


15 lOg 


17 6 


19 u 


20 


Si 


22 


3I 



Table of the Diameter of Wheels at the Pitch Circle — Continued. 











Pitch of the Teeth. 










Number of 
Teeth. 
























inches. 


inches. 


inches. 


inches. 


inc 


les. 


inches. 




^M 


2 


^• 


2%. 




3- 


334- 


3^. 


241 


14 Ah 


15 


Hi 


17 


6| 


19 


2| 


20 


9f 


22 


4f 


242 


14 51 


16 


0^ 


17 


71 


19 


3l 


20 


lOg 


22 


51 


243 


14 6 


i6 


If 


17 


8f 


19 


4f 


20 


iif 


22 


6| 


244 


14 6| 


16 


2^ 


17 


9^ 


19 


5^ 


21 


of 


22 


7f 


245 


14 7f 


16 


2l 


17 


io| 


19 


6f 


21 


if 


22 


8| 


246 


H H 


16 


3l 


17 


III 


19 


7f 


21 


2| 


22 


10 


247 


14 81 


16 


4i 


18 


ol 


19 


8^ 


21 


3* 


22 


iii 


248 


H 9f 


16 


5* 


18 


I 


19 


9 


21 


4-] 


23 


ol 


249 


14 lof 


16 


6| 


18 


II 


19 


9l 


21 


5^ 


23 


li 


250 


14 II 


16 


6| 


18 


2| 


19 


io| 


21 


61 


23 


2^ 


251 


14 ii| 


16 


7l 


18 


3l 


19 


III 


21 


7l 


23 


3f 


252 


15 of 


16 


8-i 


18 


4J 


20 


of 


21 


8f 


23 


4l 


253 


15 a 


16 


9i 


18 


51 


20 


II 


21 


9f 


23 


51 


254 


15 ^ 


16 


io| 


18 


6| 


20 


2i 


21 


io| 


23 


6f 


255 


15 2| 


16 


io| 


18 


7* 


20 


3^ 


21 


III 


23 


8 


256 


15 3f 


16 


III 


18 


8 


20 


4l 


22 


ol 


23 


9l 


257 


15 4 


17 


0.^ 


18 


81- 


20 


5f 


22 


If 


23 


I of 


258 


15 4| 


17 


i| 


18 


9i 


20 


6| 


22 


2k 


23 


iif 


259 


15 51 


17 


2^ 


18 


10} 


20 


7f 


22 


3l 


24 


oi 


260 


15 6} 


17 


2| 


18 


11^ 


20 


8] 


22 


As 


24 


If 


261 


15 ^ 


17 


3l 


19 


of 


20 


9i 


22 


6 


24 


2| 


262 


15 7i 


17 


4i 


19 


If 


20 


10^ 


22 


7 


24 


3s^ 


263 


15 8| 


17 


51 


19 


2^ 


20 


Hi 


22 


8 


24 


5 


264 


15 9 


17 


6 


19 


3 


21 


oi 


22 


9l 


24 


6^ 


265 


15 9| 


17 


6i 


19 


3 s 


21 


I 


22 


lo^ 


24 


71 


266 


15 io| 


17 


7f 


19 


4f 


21 


2 


22 


11* 


24 


81 


267 


15 Hi 


17 


8| 


19 


5f 


21 


2f 


23 


ol 


24 


9f 


268 


15 III 


17 


9l 


19 


H 


21 


3f 


23 


II 


24 


lOj 


269 


16 o| 


17 


10 


19 


7f 


21 


4l 


23 


21 


24 


ii| 


270 


16 If 


17 


io| 


19 


8f 


21 


5t 


23 


3f 


25 


ol 


271 


16 2 


17 


ii| 


19 


9f 


21 


6| 


23 


4f 


25 


li 


272 


l6 2| 


18 


of 


19 


10 


21 


7f 


23 


5f 


25 


3 


273 


16 3l 


18 


a 


19 


io| 


21 


8f 


23 


6f 


25 


4i 


274 


16 4\ 


18 


2 


19 


iif 


21 


9I 


23 


7f 


25 


51 


275 


16 4l 


18 


2| 


20 


of 


21 


lof 


23 


8f 


25 


61 


276 


16 51 


18 


lb. 

38 


20 


ih 


21 


11^ 


23 


9i 


25 


7i 


277 


16 6f 


18 


4f 


20 


2I 


22 


Oj 


23 


10^ 


25 


8| 


278 


16 7 


18 


5} 


20 


3f 


22 


if 


25 


III 


25 


9f 


279 


i6 71 


18 


6 


20 


Al 


22 


^8 


24 


of 


25 


I of 


280 


16 8^ 


18 


6i 


20 


5 


22 


3f 


24 


if 


25 


III 


281 


16 9l 


18 


7t 


20 


51 


22 


4f 


24 


2f 


26 


I 


282 


16 9I 


18 


8f 


20 


6| 


22 


51 


24 


3l 


26 


2| 


283 


16 lof 


18 


9* 


20 


7f 


22 


6^ 


24 


4l 


26 


3l 


284 


16 nf 


18 


9l 


20 


8i 


22 


7l 


24 


51 


26 


4f 


285 


17 oj 


18 


lof 


20 

8 


9f 
I 


22 


8i 


24 


6| 


26 


5^ 



Table of the Diameter of Wheels at the Pitch Circle — Continued. 









Pitch of the Teeth. 








Number of 
Teeth. 


















inches. 


inches. 


inches. | 


inches. 


inches. | 


inches. 




2%. 


2>^- 


23 


^■ 


3- 


3^/ 


{• 


3^. 


286 


17 Of 


18 IlJ 


20 


lOf 


22 9 


24 


71 


26 6| 


287 


17 4 


19 of 


20 


"1 


22 10 


24 


8f 


26 7I 


288 


17 2i 


19 A 


21 





22 II 


24 


9i 


26 8f 


289 


17 2l 


19 li 


21 


oi 


22 \\l 


24 


lOf 


26 9I- 


290 


17 3l 


19 2f 


21 


II 


23 of 


25 





26 II 


291 


17 4f 


19 3? 


21 


2f 


23 ll 


25 


I 


27 o\ 


292 


17 5i 


19 ^\ 


21 


3f 


23 2f 


25 


2 


27 If 


293 


17 5f 


19 5J 


21 


4f 


23 3I 


25 


3* 


27 2f 


294 


17 6^ 


19 5l 


21 


5^ 


23 4l 


25 


4f 


27 3? 


295 


17 7i 


19 6| 


21 


6i 


23 5f 


25 


5^ 


27 4f 


296 


17 7f 


19 7j 


21 


7 


23 6| 


25 


6i 


27 51 


297 


17 8| 


19 8| 


21 


71 


23 7l 


25 


1\ 


27 6f 


298 


17 9l 


19 9* 


21 


8f 


23 8^ 


25 


8i 


27 ll 


299 


17 lOj 


19 9\ 


21 


9t 


23 9| 


25 


9f 


27 9i 


300 


17 \ol 


19 lof 


21 


io| 


23 I of 


25 


io| 


27 io|^ 



82 



Weight of Cast Iron Balls from i to 12 Inches Diameter. 



Size. 


Wt. 


Size. 


Wt. 


Size. 


Wt. 


Size. 


Wt. 


Size. 


Wt. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


I 


.136 


Z\ 


5.84 


6 


2945 


8^ 


83-73 


H 


181.48 


^h 


.460 


4 


8.72 


6^ 


37-44 


9 


99-4 


Hi 


207-37 


2 


1.09 


\h 


12.42 


7 


46.76 


9* 


116.9 


12 


235-62 


2h 


2.13 


5 


17.04 


lh 


57-52 


10 


136.35 






3 


3.68 


5^ 


22.68 


8 


69.81 


10^ 


157-84 







Weight of 


Cast Iron Pipes 12 Inches Lon 


gjrom 


\toi\ 


Inch Thick. 


Diam. 


Inch. 


Inch 


Inch. 


Inch. 


Inch. 


Inch. 


Inch. 


Inch. 


Inch. 


of Bore. 


% 


% 


K 


% 


% 


% 


I 


^y^ 


^% 


Inch. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


I 


3-06 


5.06 


7-36 


9-97 


12.89 


16. II 


19-63 






li 


3-68 


5.98 


8.59 


11.51 


14-73 


18.25 


22.09 






I^ 


4.29 


6.9 


9.82 


13-04 


16.56 


20.4 


24.54 


28.99 


33.74 


I^ 


4.91 


7-83 


11.05 


14-57 


18.41 


22.55 


27. 


31-75 


36.76 


2 


5-53 


8-75 


12.27 


16.11 


20.25 


24-7 


29-45 


34-46 


39-89 


2i 


6.14 


9.66 


13-5 


17.64 


22.09 


26.84 


31-85 


37-28 


42.95 


2^ 


6.74 


10.58 


14.72 


19.17 


23-92 


28.93 


34.36 


40.03 


46.02 


2t 


7.36 


II-5 


15-95 


20.7 


25-71 


31-14 


36.81 


42.8 


49.08 


3 


7.98 


12.43 


17.18 


22.19 


27.62 


33-29 


39.28 


45-56 


52.16 


3i 


8-59 


13-34 


18.35 


23-78 


29-45 


35-44 


41.72 


48.32 


55-22 


3i 


9.2 


14.21 


19.64 


25-31 


Z^l> 


37-.S8 


44.18 


51.08 


58.29 


34 


9.76 


15-19 


20.86 


26.85 


ZZ-'i^Z 


39-73 


46.63 


53-84 


61.36 


4 10.44 


16.11 


22.1 


28.38 


34-98 


41.88 


49.09 


56.61 


64-43 


a\ ii-i 


17.08 


23-37 


29.97 


36.87 


44.08 


51.6 


59-42 


67-55 


4J 11.66 


17.94 


24-54 


31-44 


38.65 


46.17 


53-99 


62.12 


70.56 


4| 12.27 


18.87 


25-77 


32.98 


40.5 


48.32 


56-45 


64.89 


73-63 


5 12.88 


19.78 


26.99 


34.51 


42.33 


50.46 


58.9 


67.64 


76.69 


5i 13-5 


20.71 


28.23 


36.05 


44.18 


52.62 


61.36 


70.41 


79-77 


5* 14.H 


21.63 


29-45 


37-58 


46.02 


54.76 


63.81 


73-17 


82.84 


5l 


14-73 


22.55 


30.68 


39.12 


47-86 


56.91 


66.27 


75-94 


85.91 



83 



Weight 


of Cast Iron Pipes 12 


Inches Long, from \ to 1 


\ Inch 


77iic/c- 


— Cont. 


Diam. 


Inch, 


Inch, 


Inch, 


Inch, 


Inch, 


Inch, 


Inch, 


Inch, 


Inch, 


of Bore. 


% 


% 


y^ 


% 


M 


Vs 


I 


^Ys 


I^ 


Inch. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


6 


i,S-34 


2347 


31-91 


40.65 


49-7 


59.06 


6873 


78.7 


88.75 


6^ 


IS-9,S 


24-39 


33-13 


42.18 


51-54 


6l.2I 


71.18 


81.23 


92.04 


6i 


i6.';7 


25-31 


34-36 


43-72 


53-39 


63-36 


73-41 


84.22 


95-1 


6| 


17.18 


26.23 


35-59 


45.26 


55-23 


65.28 


76.09 


86.97 


98.18 


7 


17.79 


27-15 


36.82 


46.79 


56.84 


67-65 


78-53 


89-74 


101.24 


7i 


18.41 


28.08 


38.0s 


48.1 


58-91 


69-79 


81. 


92-5 


104.31 


7^ 


iq.OT, 


29. 


39-05 


49.86 


60.74 


71-95 


83-45 


95.26 


107.38 


7f 


iq.64 


29.69 


40.5 


5 1 -38 


62.59 


74.09 


85-9 


98.02 


110.45 


8 


20.02 


30.83 


41.71 


52.92 


64.42 


76-23 


88.35 


100.78 


113-51 


8} 


20.86 


31-74 


42.95 


54-45 


66.26 


78.38 


90.81 


103.54 


116.58 


8.V 


21.69 


32-9 


44-4 


56.21 


68.33 


80.76 


93-49 


106.53 


119.87 


8f 


22.09 


33-59 


45-4 


57-52 


69-95 


82.68 


95-72 


109.06 


122.72 


9 


22.71 


.34-52 


46.64 


5907 


71.8 


84.84 


98.18 


1 1 1.84 


125.8 


P} 


2.3-.V 


35-43 


47-86 


60.59 


73-63 


86.97 


100.63 


114-59 


128.85 


q^ 


2?,m 


36-36 


49.09 


62.13 


75-47 


89-13 


103.09 


117-35 


131-93 


9l 


24- "iS 


37.28 


50-32 


63.66 


77-32 


91.28 


105.54 


120.12 


134-99 


lO 


25.16 


38.2 


51-54 


65-2 


79.16 


93-42 


108. 


122.87 


138.06 


lo^ 


2S.77 


39-11 


52-77 


66.73 


80.99 


95-57 


110.44 


125.63 


141. 12 


io| 


26. s8 


40.04 


54- 


68.26 


82.84 


97.71 


112. 9 


128.39 


144-19 


io| 


27. 


40.96 


55-22 


69.8 


84.67 


99.86 


115-35 


131-15 


147.26 


II 


27.62 


41.88 


56.46 


71-33 


86.52 


102.01 


117.81 


133-92 


150.33 


"i 


28.22 


42.8 


57-67 


72.86 


88.35 


104.15 


120.26 


136.67 


153-4 


lU 


28.84 


43-71 


58.9 


74-39 


90.19 


106.3 


122.71 


139-44 


156.44 


"f 


29.4s 


44-64 


60.13 


75-93 


92.04 


108.45 


125.18 


142.18 


159-54 


12 


30.06 


45-55 


61-35 


77-46 


93-6 


110.6 


127.6 


144.96 


162.6 



Weight of Cast Iron Pipes 12 Inches Long, from i^ to i^ Inch Thick. 



D. of B. 


1% Inch. 


1% Inch. 


D. of B. 


1% Inch. 


ii^ Inch. 


D.ofB. 


1% Inch. 


Inch. 


lbs. 


lbs. 


Inch. 


lbs. 


lbs. 


Inch. 


lbs. 


2\ 


48.94 


55-22 


51 


9596 


106.77 


9 


140.06 


2h 


52.30 


58.9 


6 


99-56 


110.44 


9i 


143-43 


2} 


55.68 


62.58 


6i 


102.92 


II4.I3 


9h 


146.8 


3 


59.06 


66.27 


6^ 


106.31 


II7.81 


9i 


150.18 


3i 


62.43 


69.95 


6| 


109.68 


121.49 


10 


153-55 


3^ 


65.81 


73-63 


7 


11305 


125.17 


io| 


156.92 


3'^ 


69.18 


77-31 


7k 


116.43 


128.86 


10^ 


160.3 


4 


72.56 


81. 


lh 


119. 81 


132-54 


io| 


163.67 


4} 


75-99 


84-73 


Ti 


123.18 


136.22 


II 


167.06 


4* 


79-3 


88.35 


8 


126.55 


139.89 


Hi 


170.4 


4f 


82.68 


92.04 


8i 


129.92 


143-58 


11^ 


173-8 


5 


86.05 


95-72 


8^ 


13353 


147-49 


iif 


177.18 


S^ 


89.44 


99.41 


8i 


136.68 


150.94 


12 


180.54 


Si 


92.81 


102.86 













i^ Inch. 

lbs. 
154-64 
158.3 
161.99 
165.67 

169-35 

173-03 

176.71 

180,4 

184.06 

187.76 

191.44 

195.12 

198.8 



84 



Round Cast Iron Twelve Inches Long. 



Size. 


Weight. 


Size. 


Weight. 


Size. 


Weight. 


Size. 


Weight. 


Size. 


Weight. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


h 


.61 


A 


12.42 


4 


39-27 


51 


81.14 


9 


198.79 




•95 


2t 


13.84 


4^ 


41.76 


5^ 


84.71 


9i 


210. 


\ 


1.38 


2h 


15-33 


4i 


44.27 


6 


88.35 


9h 


221.5 


i 


1.87 


2| 


16.91 


4t 


46.97 


6] 


95-87 


9if 


23334 


I 


2.45 


2f 


18.56 


4* 


49-7 


6* 


103.69 


10 


245-43 


a 


31 


2^ 


20.28 


4^ 


52.5 


6i 


III.82 


loi 


257.86 


I^ 


3-«.3 


3 


22.08 


4f 


55-37 


7 


120.26 


loi 


270.59 


If 


4.64 


3i 


23.96 


4^ 


5^-32 


1\ 


129. 


io| 


283.63 


A 


5-52 


3i 


25.92 


5 


61-35 


n 


138.05 


II 


296.97 


if 


6.48 


3t 


27-95 


5i 


64.46 


n 


147.41 


Hi 


310.63 


If 


7-51 


3^ 


30.06 


5i 


67.64 


8 


157.08 


la 


32459 


I^ 


8.62 


3l 


32.25 


51 


70.09 


^\ 


167.05 


Ilf 


338.85 


2 


9.81 


3f 


34-51 


Sh 


74-24 


8i 


177. 1 


12 


353-43 


2i 


11.08 


3i 


36.85 


S% 


77-65 


8| 


187.91 







Square Cast Iron Twelve Inches Long. 



Size. 


Weight. 


Size. 


Weight. 


Size. 


Weight. 


Size. 


Weight. 


Size. 


Weight. 


:inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


Inch. 


lbs. 


h 


.78 


2i 


15.81 


4 


50. 


5f 


103.32 


9 


253-12 


% 


1.22 


2t 


17.62 


4i 


53-14 


5i 


107.86 


9} 


267.38 


i 


1-75 


2\ 


19.53 


4i 


56.44 


6 


112. 5 


9^ 


282. 


8 


2-39 


2f 


21.53 


4l 


59.81 


6i 


122.08 


9| 


297.07 


1 


3.12 


2f 


23-63 


Ah 


63.28 


64 


132.03 


10 


312.5 


li 


3-95 


2^ 

^8 


25.83 


4t 


66.84 


6f 


142.38 


10} 


328.32 


li 


4.88 


3 


28.12 


4f 


70.5 


7 


153-12 


10^ 


344.53 


It 


5-9 


3i 


30.51 


4i 


74.26 


7i 


164.25 


I of 


361.13 


I^ 


7-03 


3i 


zz- 


5 


78.12 


7^ 


175.78 


II 


378.12 


l| 


8.25 


3i 


35-59 


5i 


82.08 


7f 


187.68 


Hi 


395-5 


If 


9-57 


3i 


38.28 


5i 


86.13 


8 


200. 


la 


413.28 


li 


10.98 


31 


41.06 


5t 


90.28 


8} 


212.56 


"1 


431.44 


2 


12.5 


3^ 


43.94 


5i 


94.53 


8^ 


225.78 


12 


450. 


2^ 


14.11 


3i 


46.92 


5? 


98.87 


8| 


23925 







85 



Flat Cast Iron Twelve Inches Long, \ to I Inch Thick. 



Width of 


Inch. 


Inch. 


Inch. 


Inch. 


Inch. 


Inch. 


Inch. 


Iron. 


M 


% 


% 


% 


% 


Vs 


I 


Inch. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


2 


1.56 


2.34 


3.12 


3-9 


4.68 


5-46 


6.25 


2i 


1-75 


2.63 


3-51 


4-39 


5-27 


6.15 


7-03 


2^ 


1-95 


2.92 


3-9 


4.88 


5.85 


6.83 


7.81 


23. 


2.14 


3.22 


4.29 


5-37 


6.44 


7.51 


8.59 


3 


2.34 


3-51 


4.68 


5.85 


7-03 


8.2 


9-37 


3i 


2.53 


3.8 


5.07 


6.34 


7.61 


8.88 


10.15 


3h 


2.73 


4-1 


5.46 


6.83 


8.2 


9.57 


10.93 


3i 


2.93 


4-39 


5.85 


7.32 


8.78 


10.25 


11.71 


4 


3.12 


4.68 


6.25 


7.81 


9-37 


10.93 


12.5 


4i 


332 


4.97 


6.64 


8.3 


9.96 


11.62 


13.28 


4i 


3-51 


5.27 


7.03 


8.78 


10.54 


12.3 


14.06 


4^ 


3-71 


5-56 


7.42 


9.27 


II. 13 


12.98 


14.84 


5 


3-9 


5.86 


7.81 


9.76 


11.71 


13.67 


15.62 


5i 


4.1 


6.15 


8.2 


10.25 


12.3 


14.35 


16.4 


5^ 


4.29 


6.44 


8.59 


10.74 


12.89 


1503 


17.18 


5f 


4.49 


6.73 


8.98 


11.23 


13.46 


15-72 


17.96 


6 


4.68 


7.03 


9-37 


II. 71 


14.06 


16.4 


18.75 



Weight 


of a Superficial 


Foot of 


Cast Ironfron 


I \ to 2 Inches Thick. 


Thickness. 


y^ 


% 


% 


% 


% 


% 


I 


^% 


Wt. 


lbs. 

9.37 


lbs. 

14.06 


lbs. 
18.75 


lbs. 
23-43 


lbs. 

28.12 


lbs. 

32.81 


lbs. 

37.5 


lbs. 

42.18 



Thickness. 


^M 


1% 


xK 


^% 


1% 


1% 


2 




Wt. 


lbs. 
46.87 


lbs. 
51-56 


lbs. 
56.25 


lbs. 

60.93 


lbs. 
65.62 


lbs. 

70.31 


lbs. 

75- 





86 



Weight of Square Lead Twelve Inches Long, from I to ^ Inches Square. 



Size. 


I in. 


X>8 


i^ 


1% 


^y, 


1% 


1% 


1% 


2 




lbs, 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


Wt. 


4-93 


6.25 


7.71 


9-33 


II. II 


13.04 


15.12 


17.36 


19.75 




Size. 


^Vs 


2^ 


2% 


--X 


2^/^ 


2% 


2% 


3 






lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 




Wt. 


22.29 


25. 


27.8 


30.86 


34.02 


37.34 


40.81 


^AAA 




Weight of Round Lead Tivet 


't^^ Inches Long, from 1/^3 Inches Diameter. 


Size. 


I in. 


1% 


i^ 


1% 


^y^ 


^% 


1% 


1% 


2 




lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


Wt. 


3-87 


4.9 


6.06 


7.33 


8.72 


10.24 


11.87 


13.63 


15-51 




Size. 


^Vs 


2)4 


2% 


2>^ 


2% 


2% 


2% 


3 






lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 


lbs. 




Wt. 


17.51 


19.63 


21.8 


24.24 


26.72 


29.33 


32.05 


34.9 




Binary and Decimal Fractions. 


^\ =.015625 


23 
04 




=.359375 


\\ =.6875 


3L =.03125 




1 

8 


=•375 


If =.703125 


^\ =.046875 


25 




=.390625 


If =.71875 


tV =.0625 




M 


=^.40625 


II =.734375 


?\ =.078125 


H 




= 421875 


\ =.75 


3% =-09375 




tV 


=•4375 


If =765625 


sV =.109375 


29 

6T 




=•453125 


ft =.78125 


i =-125 




15 

32 


= 46875 


%\ =.796875 


■s% =.140625 


31 




=.484375 


if =.8125 


3^ =.15625 




h 


=.5 


If =828125 


H =.171875 


33 

6¥ 




=.515625 


11 =-84375 


t\ =-1875 




H 


=.53125 


If =.859375 


if =.203125 


35 
61 




= 546875 


I =.875 


3V =.21875 




9 

T6 


=.5625 


fl =.890625 


if =.234375 


37 
6¥ 




= 578125 


ft =.90625 


i =.25 




1 9 
32 


=.59375 


If =.921875 


H =.265625 


39 




=.609375 


\\ =.9375 


/^ =.28125 




5 


=.625 


%\ =-953125 


if =.296875 


H 




=.640625 


fl =.96875 


t'^ =.3125 




21 

3 2 


=.65625 


If =.984375 


fi =.328125 


e 




=.671875 


I =1.000000 


1 1 


^^^. 


34375 


I 








1 









87 





Distances 


at which to op 


"n a 2 


ft. Rule to obtain a given Angle. 


Angle. 


Distance. 


Angle. 


Distance. 


Angle. 


Distance. 


Angle. 


Distance. 


Angle. 


Distance. 


Deg. 


Inches 


Deg. 


Inches 


Deg. 


Inches 


Deg. 


Inches 


Deg. 


Inches 


I 


.2 


19 


3-96 


37 


7.61 


55 


1 1.08 


11 


14.28 


2 


•42 


20 


4-17 


38 


7.81 


56 


11.27 


74 


14.44 


3 


•63 


21 


4-37 


39 


8.01 


57 


11.45 


75 


14.61 


4 


.84 


22 


4-58 


40 


8.20 


58 


11.64 


76 


14.78 


5 


1.05 


23 


4.78 


41 


8.40 


59 


11.82 


77 


14.94 


6 


1.26 


24 


4-99 


42 


8.60 


60 


12.00 


78 


15. II 


7 


1-47 


25 


519 


43 


8.80 


61 


12.18 


79 


15-27 


8 


1.67 


26 


540 


44 


8.99 


62 


12.36 


80 


15-43 


9 


1.88 


27 


5.60 


45 


9.18 


63 


12.54 


81 


15-59 


lO 


2.09 


28 


5.81 


46 


9-38 


64 


12.72 


82 


15-75 


II 


2.30 


29 


6,01 


47 


9-57 


65 


12.90 


^Z 


15.90 


12 


2.51 


30 


6.21 


48 


9.76 


66 


13.07 


84 


16.06 


13 


2.72 


31 


6.41 


49 


9-95 


67 


1325 


85 


16.21 


14 


2.92 


32 


6.62 


50 


10.14 


68 


1342 


86 


16.37 


15 


Z'^Z 


z-h 


6.82 


51 


10.33 


69 


13.59 


87 


16.52 


i6 


3-34 


34 


7.02 


52 


10.52 


70 


13.77 


88 


16.67 


17 


3.55 


35 


7.22 


53 


10.71 


71 


13.94 


89 


16.82 


i8 


3.75 


36 


7.42 


54 


10.90 


72 


I4.II 


90 


16.97 



88 



French Aletre reduced to Inches. 





« 


1 (ft 












Metre. 


11 



n 




Metre. 




Inches. 




Feet. 


.001587 


1 


I = 


.001 


= 


•03937 


= 


.00328 


.00317 


= ¥ 


2 = 


.002 


= 


.07874 


= 


.00656 


.00476 


— _3_ 


3 = 


,003 


= 


.ii8n 


= 


.00984' 


.00635 


= i 


4 = 


.004 


= 


.15748 


= 


.01312 


.00794 


= t\ 


5 = 


.005 


= 


.19685 


= 


.01641 


.00952 


= t 


6 = 


.006 


= 


.23622 


= 


.01969 


.0111 I 


— t'g 


7 = 


.007 


:== 


.2756 


= 


.02397 


.01270 




8 = 


.008 


= 


•31497 


= 


.02625 


.01429 


9 


9 = 


.009 


= 


•35434 


= 


.02953 


.01587 


-^ s" 


.i <" 












.01746 


1 1 

— 1 6 














.01905 


3 

— 4 


^6 












.02064 


13 

— 1J5 


I = 


.01 


= 


•3937 


= 


.0328 


.02222 


= i 


2 = 


.02 


= 


.7874 


= 


.0656 


.02381 


15 

— 11; 


3 = 


•03 


= 


1.1811 


= 


.0984 


.02540 


= I 


4 = 


.04 


= 


1^5748 


= 


.1312 


.05078 


= 2 


5 = 


•05 


= 


1.9685 


= 


.1641 


.0762 


= 3 


6 = 


.06 


= 


2.3622 


= 


.1969 


.1016 


= 4 


7 = 


.07 


= 


2.756 


= 


•2397 


.1270 


= 5 


8 = 


.08 


= 


3-1497 


= 


.2625 


•1524 


= 6 


9 = 


.09 


= 


3-5434 


— 


-2953 


.1778 


= 7 


1 <n 












.2032 


= 8 


1) 13 












.2286 


= 9 


fi'g 












.2540 


= lO 


I = 


.1 


= 


3-9371 


=: 


-3281 


.2794 


= II 


2 = 


.2 


= 


7.8742 


= 


.6562 


,3048 


= 12 


3 = 


--> 
•J 


=: 


11.8112 


= 


-9843 






4 = 


•4 


= 


15-7483 


= 


1-3124 






5 = 


•5 


= 


19.6854 


= 


1.6404 






6 = 


.6 


= 


23.6225 


:= 


1.9685 






7 = 


•7 


= 


27^5596 


= 


2.3966 






8 = 


.8 


= 


31.4966 


= 


2.6247 






9 = 


•9 


r= 


35^4337 


= 


2.9528 



The Metre = 3.2808992 Feet (about 39! Inches). 



89 



PLATES OF GEAR TEETH 



13 I'.'r. 



14 'l.'P. 



I 



1-80 




t5 ii."i». 




10 to 17 T't. 




18 to If) 1. r. 



•34 



2-4S 



90 to 21 t: p. 



35 

1-81 



i 



A 



22 to 24 I'.'r. 



■36 



1-34 



23 to 27 I'.'P. 



1-07 



L i 



28 to 31 i: r 




32 to 55 I'.'P 36 to 41 l[' P. 





42 to 47 l'! r. 




03 to 130 i! r. I3itosoo 1.' r 




* FULL SIZE GEAR TEETH. 
/'>om Prof. S. IV. Robinson's Templet Odontograph. 



1 3 iH'.'-'P . 14 IH'.'Ji 



j40 
4-7G' 




22 to 2'4 1M'.' r. 



15 IH. P. 




16 to 17 V4''P, ^^ fo ^^ IVi' P- 20 to 21 1%'.' T 




•42 



3-10 



2 -20 



25 to 27 IH'.' 7*. 28to311H.P 



•46 



r84 



J 



32 to 35 IH. P. 



3G to 41 IM. r. 42 to 47 IH. P. 



•4!) 



1-05 



•% 




FULL SIZE GEAR TEETH. 

From Prof. S. V/. Robinson's Templet Odontograph, 




18 to 19 iyz:F: 20 fo21t^. T 



3-72 



22 to 24 VA, P. 



52_ 

2-70 



_i- 



"•51 



2-01 



i 



2S to 27 IVz'.'P. 28 to 31 iVz. P. ^^ to 3. ? l\i. P 



•55 



1^60 



i 




FULL SIZE GEAR TEETH. 

F)-oiii Prof. S. W. Rob ins oil's Templet Odontograph, 




48 to 62 VA. P. 



14 iH. r 



( 

•50 


\ 


G-G7 




" 


1, 



•64 



■96 



G3 t o 130 IH '.'P. t31 to SOO iVz' P. 




15 IH'.'P. 10 to 17 IH'.'P. 



is to 19 1%: P. 





FULL SIZE GEAR TEETH. 

From Prof. S. W. Robinson'' s Templet Odontograph, 



2S to 2t IH. r 



2S to 31,1H. r. 



32 to 35 lU'.'jP. 




63 tr> 130 1H'. P 




131 to soo ml' P. 




FULL SIZE GEAR TEETH. 
J^rom P^of. S. W. Robinson's Templet Odontograph, 



14 2:r. 





22 to 24 2.' P. 



1 

•72 


\ 




2-68 




\ 









FULL SIZE GEAR TEETH. 
From Prof. S. \V. Robinson'' s Templet Odontograph. 



2S to 27 2': r. 




2S to 31 2.' P. 



( 

•7G 


\ 


18G 

/ 





36 to 41 a'.' P. 




FULL SIZE GEAR TEETH. 

I^rotn Prof. S. IV. Robinson's Templet Odontograph. 



e3 to ISO 2.' P 



13 1 to SOO S.T. 




FULL SIZE GEAR TEETH. 

J^rom Prof. S. IV. Eobinsoiis Templet Odontograph. 



20 to 21 i2H.R.. 



22 to 24 2H. P. 



•79 


\ 


4-07 









23 to 27 2H: r. 




FULL SIZE GEAR TEETH. 

J^7'0f)i Prof. S. W. Robinson's Templet Odontograpk. 



42 to 47 2\i! P. 



•93 



63 to 130 2H. P 



48 to 62 2H. -P. 



1-44 



131 to SOO 214'.' P. 




FULL SIZE GEAR TEETH. 

F^om Prof. S. JF. Robinson s Templet Odoiitograph. 



14 2H'/JP 




16 to i: 


r 2%: p. 


( 

•R2 


\ 


8-37 


—] 



18 to If) 2H. r. 




FULL SIZE GEAR TEETH. 
F7'oin Prof. S. IV. Robinson^ s Templet Odoniograph. 



20 to 21 2M. P. 



22 to 24 Sh'.'r. 




FULL SIZE GEAR TEETH. 
J^rom Prof. S. W. Rohinsott' s Te7nplet Odontograph. 



32 to 35 2H:'r 




FULL SIZE GEAR TEETH. 
Frow Prof. S. W. Robinson's Templet Odontograph. 



03 to 130 314. r. 



I 
131 to soo 2H'.'r. 



I 

1-10 


1-17 


\ 


1-42 

/ 


1-25 


\ 









11 2H\ r 




FULL SIZE GEAR TEETH. 

Fj'OJn Prof. S. IV. Robinson s Templet Odonfograph. 




FULL SIZE GEAR TEETH. 
Fro7ii Prof. S. IV. Robinson'' s Templet Odontograph. 



25 to 27 2H'.' p. 



2S to 31 2H'.'I\ 



1-01 
2-94 



2-55 



32 to 35 2h:P 




FULL SIZE GEAR TEETH. 
From Prof. S. W. Robinson'' s Templet Odontograph. 



42 to 47 2U''r 




63 to 130 2H. r. 



131 to 800 2%: P. 



1-21 


1 1-20 


\ 


1-5C 


l'o7 


\ 


1 







FULL SIZE GEAR TEETH. 

Fro/n-Prof. S. W. Robinsons Templet Odontograph, 



14 s'.'r. 




la s'.'r. 




FUIX SIZE GEAR TEETH. 

F7'o/ii Prof. S. W. Robinson s Templet Odontograph. 



22 to 24 3. r. 




FULL SIZE GEAR TEETH. 
from Prof. S. W. Robinsons Templet Odontograph. 




FULL SIZE GEAR TEETH. 

From Prof. S. W. Robinson's Templet Odontograph. 




FULL SIZE GEAR TEETH. 

From Prof. S. W. Robinson's Templet Odoniograph. 




FULL SIZE GEAR TEETH. 
From Prof. S. IF. Robinson's Te?npJct Odonfoo-raf>/i. 



